TS-26: Technical writing style guide

This technical standard covers how to write technical documentation. Topics include voice and tense, headings, terminology, formatting conventions, and other prose-level and presentational rules that apply within any individual document.

For what documentation a project should have, where it lives, who it’s for, and how it’s kept current, see TS-25: Technical documentation.

Contents

Voice and tense
- Normative language
Headings
Terminology
Abbreviations and acronyms
Inclusive and plain language
Emphasis
- Titles of works
- Foreign words
Admonitions
Lists
Links
Numbers, dates, and units
Code blocks
Referencing
Punctuation
Sentences and paragraphs
AI writing tells
Glossary
- Commonly confused words
- A
- B
- C
- D
- E
- F
- G
- H
- I
- J
- K
- L
- M
- N
- O
- P
- Q
- R
- S
- T
- U
- V
- W
- X
- Y
- Z
- Countries and nationalities
- Transliteration of foreign names
- Honorifics and personal titles
Grammar
References

Voice and tense

Prefer active voice over passive voice. "The server rejects invalid requests" is clearer than "invalid requests are rejected by the server." Passive voice is acceptable when the actor is genuinely unknown or irrelevant to the point being made.

Prefer present tense when describing current system behavior: "the function returns null" rather than "the function will return null." Reserve future tense for describing what will happen as a consequence of an action the reader takes, and past tense for historical records such as changelogs.

Address the reader directly as "you" in instructional content ("run the following command") rather than an impersonal construction ("the user should run the following command"). This keeps instructions unambiguous about who is meant to act.

Avoid first-person plural ("we") to refer to the software itself – "the API returns an error," not "we return an error." Reserve "we" for genuine statements of the author’s or team’s position, such as in a design rationale.

Recognize passive voice by its verb phrase: a form of "be" (am, is, are, was, were, been) followed by a past participle, with the sentence’s subject receiving the action rather than performing it. As a check, try appending "by <actor>" — a passive sentence accepts it without changing meaning ("invalid requests are rejected [by the server]"), where an active sentence does not. A be-verb alone does not make a sentence passive: "the service was running for six hours" is active (past progressive), since "the service" is doing the running, not receiving it.

Use contractions ("it’s," "don’t," "can’t") where they make a sentence read more naturally, but do not overuse them to the point that the document reads as informal or conversational rather than as technical reference material.

Normative language

Use the RFC 2119 requirement keywords — MUST, MUST NOT, REQUIRED, SHALL, SHALL NOT, SHOULD, SHOULD NOT, RECOMMENDED, MAY, and OPTIONAL — in body prose to express an obligation, a prohibition, or a genuine option, rather than a softer everyday phrasing such as "should probably" or "it’s a good idea to." Render each keyword in capitals as shown; do not use the mixed-case spelling ("Must," "should not") that some style guides prefer. A document that relies on these keywords MUST state, once, near its start, that they carry the meanings defined in IETF RFC 2119 — for example: "The keywords MUST, MUST NOT, REQUIRED, SHOULD, SHOULD NOT, RECOMMENDED, MAY, and OPTIONAL in this document are to be interpreted as described in IETF RFC 2119." Do not use a bare "must" or "should" as if it carried RFC 2119 weight in a document that has not made this declaration; without it, the keyword reads as plain English and carries no more force than any other verb.

Headings

Use sentence case for headings ("Referencing style guides"), not title case ("Referencing Style Guides"). Sentence case is faster to read, easier to write consistently, and avoids the ambiguity of which words to capitalize in a title-case scheme.

This applies equally to document titles, not just section headings within a document. Capitalize only the first word and any proper nouns: "Distributed system design", "Amazon Web Services (AWS)".

Headings SHOULD describe the content that follows, not tease it or ask a question. Prefer "Configuration options" over "What can you configure?"

Do not skip heading levels (for example, jumping from a level-1 heading to a level-3 heading). This breaks the document outline and assistive-technology navigation. Nest headings only as deeply as the content actually warrants. A document with only two or three headings does not need every level of the hierarchy.

Do not set any part of a heading in monospace, bold, or italic. A heading is already visually distinct by its size and weight, and inline formatting on top of that is redundant and can confuse a table-of-contents or search-index extraction that strips formatting inconsistently. Write Configuring the LOG_LEVEL variable in a heading, not Configuring the LOG_LEVEL variable in monospace.

Expand an acronym in a heading unless it is common enough that the target audience would recognize it unexpanded — "Configuring the content delivery network (CDN)" on first mention, but "HTTP status codes" needs no expansion. This follows the same judgment call as first-use spelling-out elsewhere in a document; see Abbreviations and acronyms.

Terminology

Use one term per concept, consistently, throughout a document and ideally across a body of documentation. Do not vary vocabulary for the sake of stylistic variety – "endpoint," "route," and "handler" should not be used interchangeably to refer to the same thing, because a reader will assume a change in wording signals a change in meaning.

Where a project has domain-specific or otherwise non-obvious terms, maintain a glossary and link to it on first use within a document rather than redefining the term inline every time.

Prefer the simpler, more common word where two words mean the same thing in context – "use" over "utilize," "help" over "facilitate," "start" over "initiate." Plain words are easier to translate, skim, and understand for non-native readers.

Preserve the original capitalization of a product, tool, or binary name as its owner writes it — write Markdown, not markdown; GitHub, not Github or github — even where that breaks the sentence-case convention in Headings or normal mid-sentence lowercasing. A proper noun keeps its own capitalization regardless of where in a sentence or heading it falls.

Abbreviations and acronyms

Spell out an abbreviation or acronym in full the first time it’s used within a document, with the short form in parentheses, and use the short form thereafter: "content delivery network (CDN)."

Exceptions are acronyms so common in a software engineering context that spelling them out would be noise to the target audience (for example, HTTP, URL, JSON). Use judgement based on the document’s audience.

Do not invent new abbreviations for a document unless they will be used often enough within it to justify the reader learning them. A one-off abbreviation saves the writer a few keystrokes at the cost of the reader’s comprehension.

Write "eg" and "ie" without periods and without a following comma: "eg the staging and production environments," not "e.g., the staging and production environments." Spell out "for example" or "that is" instead where the document is not already dense with abbreviations.

Form the plural of an abbreviation by adding a lowercase "s," with no apostrophe: "three APIs," "two CDNs" — see Apostrophes. Choose "a" or "an" before an abbreviation by how it’s pronounced, not how it’s spelled: "an HTTP request" (pronounced "aitch"), "a URL" (pronounced "you"). Omit periods from an abbreviation written in capitals (API, not A.P.I.). Do not precede a pronounceable acronym with "the" where the acronym itself already functions as the noun: "JSON is a text format," not "the JSON is a text format" — though "the API returns JSON" is fine, since "API" there is a countable noun.

Inclusive and plain language

Prefer neutral terminology over terms with violent, ableist, or otherwise unnecessary connotations where a clear alternative exists and is in common use – for example, "allowlist/denylist" over "whitelist/blacklist," "primary/replica" over "master/slave." The goal is precision and professionalism, not euphemism for its own sake.

But where an established technical term has no accepted neutral alternative, do not force an awkward substitute.

Avoid idioms, sports metaphors, and culturally specific references that may not translate for an international or non-native-English-speaking audience. Plain, literal language is more reliably understood than a colorful turn of phrase.

Write in a way that assumes competence in the reader’s own domain but not in yours. Don’t talk down to an experienced engineer who is simply unfamiliar with this particular codebase.

Emphasis

Use monospace formatting for anything a reader might type or that the system might output literally: file paths, commands, flags, environment variables, code identifiers, and configuration keys. Example: set LOG_LEVEL in .env.

Use bold for UI elements the reader must interact with: button labels, menu items, field names. Also use bold to introduce a new term at its point of definition, the first time it is used in a document.

Use italics sparingly, for genuine emphasis of a word within a sentence. Do not use italics as a substitute for bold or monospace.

Do not stack multiple forms of emphasis (bold italic monospace). Pick the one that matches what the text represents.

Within a monospace span, use italic monospace for a placeholder the reader must substitute (<file>) and regular monospace for a value the reader types or the system outputs literally, per Placeholders. Do not italicize a plain-prose mention of a URL or file name; set it in regular monospace instead, consistent with the rule above.

Titles of works

Set the title of a standalone work — a book, a paper, a film, a full publication — in italics: "Designing Data-Intensive Applications." Set the title of a work that is part of a larger publication — an article, a chapter, a blog post, a section — in quotation marks instead: "the article 'Falsehoods Programmers Believe About Time.'" See Referencing for how a title is formatted within a citation specifically, which follows this same split.

Foreign words

Italicize a foreign word or phrase that has not been absorbed into everyday English usage, and preserve its native accents and diacritics: "the API uses a naïve Bayes classifier." Do not italicize a loanword that has become standard English vocabulary, such as "cafe" or "role" — write these in plain roman type. Where a word’s status is genuinely ambiguous, follow its spelling in an authoritative English dictionary rather than the source language’s orthography.

Admonitions

Use admonition blocks (NOTE, TIP, IMPORTANT, WARNING, CAUTION) to call out information that a reader could reasonably skip in a linear read-through but should not miss – not as a substitute for well-organized prose.

Available admonitions in AsciiDoc are:

NOTE: Supplementary information that adds context but isn’t required to complete the task at hand.
TIP: An optional suggestion that makes the task easier or faster.
IMPORTANT: Information required to complete the task correctly; skipping it leads to a wrong but not necessarily harmful outcome.
WARNING: An action or condition that could cause data loss, security exposure, or other significant harm.
CAUTION: A risk of a less severe but still undesirable outcome, such as a deprecated approach.

[NOTE]
====
Supplementary context goes here.
====

Use admonitions sparingly, for genuine asides that are secondary to a linear read-through of the document – not for core content that belongs in a regular paragraph. A document with an admonition on every paragraph trains readers to skip them all.

See TS-28: AsciiDoc for the full admonition syntax, including the complex block form.

Lists

Use a numbered list when the order of items matters, such as steps in a procedure. Use a bulleted list when the order does not matter.

Keep list items grammatically parallel. If the first item starts with an imperative verb, every item should. Do not mix sentence fragments with full sentences in the same list.

Punctuate list items as sentences (capitalized, full stop) when any item is a full sentence. Terminate the lead-in sentence with a period, not a colon or dash; see Colons for why.

Before deploying, complete the following checks.

* Run the full test suite and confirm it passes.
* Review the changelog for breaking changes.
* Notify the on-call engineer of the deployment window.

Rarely, items in a list may not form proper sentences. This is acceptable where the list items are the names of things in a collection.

The following browsers are supported.

* Chrome
* Firefox
* Safari
* IE 10+
* Edge

Avoid nesting lists more than two levels deep. Restructure into subsections instead, since deeply nested lists are hard to scan.

Where nesting is warranted, mark the nested level with an em dash rather than a second round of bullet characters, so the two levels stay visually distinct at a glance:

* Supported runtimes
  — Node.js 20 and later
  — Python 3.11 and later
* Supported operating systems
  — Linux
  — macOS

Convert a bulleted list whose items are each a short term and its definition into an AsciiDoc description list instead of a plain bulleted list, since a description list renders the term and definition with distinct styling that a bulleted list cannot express:

Spellchecking:: The process of checking a document for misspelled words.
Kerning:: The process of adjusting the space between characters in a font.

Links

Link text SHOULD describe the destination, not the act of clicking. Prefer "see the deployment guide" over "click here" or a bare URL. Descriptive link text remains meaningful out of context, which matters for screen readers and for anyone scanning a page for relevant links.

Where a document will be read in both hypermedia and print/plain-text form, consider appending the full URL after the link text so the reference survives outside a hyperlinked medium.

Prefer linking to the canonical or most stable version of a resource, eg. a specific documentation version rather than a "latest" alias that will change underneath the link.

Numbers, dates, and units

Spell out numbers zero through nine in prose. Use numerals from 10 upward.

Always use numerals for measurements, versions, and anything paired with a unit (8 GB, v2, 3 retries), regardless of magnitude.

Write dates in ISO 8601 format (2026-07-02) in technical documentation, since it sorts correctly as a string and is unambiguous across locales. Avoid the MM/DD/YYYY and DD/MM/YYYY formats entirely, as both are ambiguous without knowing the writer’s locale.

Leave a space between a numeral and its unit (10 ms, not 10ms), except for percentages (10%) and degrees, which are conventionally set without a space in technical writing.

Use consistent units within a document. Do not mix, for example, milliseconds and seconds for durations of the same kind of thing without a clear reason.

Write a time of day in 24-hour format (14:30), for the same reason ISO dates are required: it sorts correctly and is unambiguous across locales, unlike 2:30pm or 2.30pm. Where a document must show 12-hour format for a non-technical audience, write it as 2:30 pm, with a space before the lowercase am/pm and no periods.

Spell out an ordinal from first through ninth; use figures with the suffix from 10th upward: "the third retry," "the 12th request." Hyphenate a spelled- out fraction used as a modifier ("a two-thirds majority") but not a figure fraction. Write "percentage points," not "percent," when stating the difference between two percentages: "latency dropped 5 percentage points, from 20% to 15%" — "dropped 5 percent" would mean a relative drop to 19%. Write a numeric range with an en dash and no surrounding spaces (10–20), per Dashes.

Code blocks

Placeholders

Prefer to use angle brackets (<>) to encapsulate any placeholder text that is intended to be swapped for a value, such as a file name or a command line argument.

Use square brackets ([]) to indicate optional arguments.

For example:

./run <script> [<script-args>]

The same convention applies inline in prose, not only inside code blocks — for example, a URL containing a variable segment: https://example.com/accounts/<account-id>/. Where the placeholder syntax needs to match a formal grammar rather than this standard’s own convention — for example, a URI Template per RFC 6570, which uses curly braces rather than angle brackets — follow that grammar instead and say so on first use: https://example.com/accounts/{account_id}/ (URI Template).

CLI commands

Do not prefix CLI commands with a dollar sign ($), as is common in many technical documents. This is because the dollar sign is not universally used to indicate a command prompt, and it can be confusing for readers who are not familiar with this convention.

In addition, some rendering systems will provide functionality for users to easily copy the content of code blocks, allowing the commands to be pasted directly into terminals. Inclusion of prompts invalidates the commands, making for a poor user experience.

```sh
git clone git@<hostname>:<group>/<project>.git
```

The exception to this rule is when documenting the output from CLI commands. In this case, including the prompt can help to clarify which lines are commands and which lines are output. Example:

$ heroku logs --help
display recent log output

USAGE
  $ heroku logs

OPTIONS
  -a, --app=app        (required) app to run command against
  -d, --dyno=dyno      only show output from this dyno type (such as "web" or "worker")
  -n, --num=num        number of lines to display
  -r, --remote=remote  git remote of app to use
  -s, --source=source  only show output from this source (such as "app" or "heroku")
  -t, --tail           continually stream logs
  --force-colors       force use of colors (even on non-tty output)

DESCRIPTION
  disable colors with --no-color, HEROKU_LOGS_COLOR=0, or HEROKU_COLOR=0

EXAMPLES
  $ heroku logs --app=my-app
  $ heroku logs --num=50
  $ heroku logs --dyno=web --app=my-app
  $ heroku logs --app=my-app --tail

Formatting

Every code block MUST specify its language on the [source,<language>] line (bash, sh, json, and so on) so syntax highlighting renders correctly; see the repository’s style guide for the full rule. Indent code with spaces, not tabs, so the block renders consistently regardless of the reader’s editor settings.

Keep a code example narrow enough to read without horizontal scrolling in a typical rendered column — wrap or truncate a long line rather than letting it run off the edge of the page.

Referencing

There are a number of conventions for including citations and reference lists within documents, such as Harvard, APA, MLA, Chicago, and Vancouver. Most conventions involve two parts:

A short inline citation within the text.
A full reference at the end of the text.

My preference is the Chicago style of placing an inline superscript number that cross-references a footnote or endnote. In hypermedia formats such as HTML, the inline citation is hyperlinked to its corresponding footnote, and vice versa, so readers can jump to the footnote and back again.

Where I want to reference works listed in a bibliography section at the end of the document, I will use the Harvard style for the inline citation. Example:

(Johnson, 2020)

The author names are written exactly as they appear in the reference list (see below).

I use the same formatting convention for references whether they appear in footnotes or bibliographies. My convention is a mix of the Chicago and Harvard styles. It places emphasis on the author and publication date:

<author> (<year>). _<title>_. <publication>

Example:

Johnson, M (2020). The Future of Learning. Horizon Press

When there are two authors, I write only their surnames:

Smith and Jones (2020). Title of the work. Publication

When there are three: "Smith, Jones, and Patel". When there are more than three authors, I will truncate to "Smith et al".

In hypermedia formats, the title may be hyperlinked. When printed, the full URL (including the https:// schema) should be appended to the end, after the publication. For academic journals it is common practice to include the issue number and page range of the source material. Example:

DeLorne and Fedler (2003). Journalists' Hostility Toward Public Relations: An Historical Perspective. Public Relations Review, volume 29, issue 2, pages 99-124. https://www.sciencedirect.com/science/article/abs/pii/S0363811103000195

For consistency, citations of press releases, news stories, and blog posts should follow the same format. However, as a general rule it is preferable to cite the organization or publisher as the author, even if the article has a byline. The following example is a reference for a company’s annual report:

Cision (2016). Inside PR 2026. https://www.cision.com/resources/guides-and-reports/2026-inside-pr-report/

The following example is a reference to a news story published on the PR Week website. The article has a byline, giving the name of the journalist who wrote the article. But it is more appropriate to cite the name of the publisher, as that is a more accurate reflection of the authorship.

PR Week (2025). Equiniti to acquire Notified from West Technology Group. https://www.prweek.com/article/1910473/equiniti-acquire-notified-west-technology-group

Footnote and endnote mechanics

Number footnotes and endnotes per document, not restarting per section or chapter, since a merged single-page standard has no natural chapter boundary to restart at. Place the footnote marker after any adjacent punctuation, not before it: "…as documented elsewhere.¹" not "…as documented elsewhere¹." A footnote MUST contain more than a bare URL — give it enough context (author, title, or a short description) that the reference is useful without following the link.

Referring to figures, tables, and examples

Do not refer to a figure, table, or code example by its position on the page ("the table above," "the diagram below"). Position is not stable across formats — a reflowable or narrow-viewport rendering can move a figure to a different position relative to the text that cites it. Refer to it by number or an explicit cross-reference instead: "see the 'Retry backoff' section," or "Table 3 lists the supported operations." Use "preceding" or "following" only where a live cross-reference genuinely isn’t available, since even those describe a position rather than pointing directly at the target.

Give every numbered figure, table, and example a caption in sentence case, with no period at the end, and refer to it specifically in the surrounding prose rather than leaving it to speak for itself — a reader scanning past figures should still get the point from the body text.

Specialized referencing conventions

A small set of domains outside general prose citation have their own established referencing conventions. Follow them rather than improvising a technical-documentation equivalent.

Latin binomial (scientific) names. Italicize the full genus-species name — Escherichia coli — with the genus capitalized and the species lowercase. After first use, the genus MAY be abbreviated to its initial: E. coli.
Classical-music works. Cite a work by its catalog designation where one exists (opus number, or a composer-specific catalog such as BWV for Bach or K. for Mozart) rather than title alone, since many classical works share a generic title: "Beethoven’s Symphony No. 5 in C minor, Op. 67," not just "Beethoven’s Fifth Symphony."
Biblical citation. Cite as <Book> <chapter>:<verse> — "John 3:16," or a range as "Romans 8:28-30." Abbreviate the book name only where the document already establishes the abbreviation on first use, following the same first-use rule as any other abbreviation — see Abbreviations and acronyms.

Punctuation

Colons

Do not use a colon to introduce a code block or a list block. Where a sentence leads into a list, terminate it with a period instead; see Lists for the list-specific guidance.

Do not use a colon to join two independent clauses that could each stand as a sentence on their own. Write them as separate sentences instead.

The only valid use for a colon is within a single sentence that ends with a short, comma-separated list.

The model supports three operations: create, read, and delete.

Lowercase the first word after a colon, unless it’s a proper noun or the colon introduces more than one complete sentence.

The model supports three operations: create, read, and delete.

Bad:

Early in a project, when the right design is not yet clear, unstructured prose is often a better problem-solving tool than code: it is more concise, faster to produce and digest, and communicates at a higher level than code can.

Good:

Early in a project, when the right design is not yet clear, unstructured prose is often a better problem-solving tool than code. It is more concise, faster to produce and digest, and communicates at a higher level than code can.

Semicolons

Prefer two separate sentences over a semicolon joining two independent clauses. A semicolon signals a closer relationship between the clauses than a full stop does, but that relationship is rarely load-bearing enough to justify the harder read. Reserve the semicolon for joining short items in a list written inline, or for the rare case where splitting the sentence would lose an explicit contrast or cause-and-effect the semicolon itself is signaling.

Bad:

The cache is invalidated on write; this keeps reads consistent with the latest data.

Good:

The cache is invalidated on write. This keeps reads consistent with the latest data.

Commas

Use the serial (Oxford) comma before the final item in a list of three or more: "create, read, and delete," not "create, read and delete." Omitting it can make the last two items read as a single pair.

Follow an introductory phrase or clause with a comma before the main clause, unless the phrase is very short (three words or fewer) and the sentence reads unambiguously without one.

After the request is authenticated, the gateway forwards it to the origin.
First look at the logs.

Do not splice two independent clauses together with only a comma. Either join them with a coordinating conjunction (and, but, so), split them into two sentences, or use a semicolon per Semicolons.

Bad:

The request failed, the client retried it.

Good:

The request failed, so the client retried it.

Quotation marks

Use plain, straight double quotes ("like this") for quoted prose, never AsciiDoc’s curly-quote syntax; see the repository’s style guide for the full rule. Use single quotes only for a quotation nested inside another quotation.

Place a period or comma that ends a quoted phrase inside the closing quotation mark, following American convention: the response returns "not found." not the response returns "not found".. A colon, semicolon, question mark, or exclamation mark goes outside the closing quotation mark unless it is part of the quoted material itself.

Apostrophes

Form a singular possessive by adding 's, including for a name ending in s: "the API’s rate limit," "Chris’s PR." Form a plural possessive by adding only an apostrophe after the existing s: "the servers' response times."

Write a decade without an apostrophe before the s: "the 2020s," not "the 2020’s." Write the plural of an abbreviation or acronym without an apostrophe: "three APIs," "two CDNs," not "three API’s."

Dashes

Use an em dash (—) closed up against the words on either side, with no surrounding spaces, to set off a parenthetical or an abrupt break in a sentence: "the change is backward compatible—no client update is required." See Stacked em dashes and bold for why this standard also treats em-dash overuse as a writing smell to avoid, independent of its mechanics.

Use an en dash (–), not a hyphen, for a numeric range or a negative number where a hyphen could be misread as a minus sign or a compound modifier: "pages 12–20," "a range of -5 to 5." Do not use an en dash as a substitute for an em dash.

Hyphenation

Hyphenate a compound modifier that precedes the noun it modifies, when leaving it open could cause the reader to misparse the sentence: "a well-defined interface," "a two-factor login." Do not hyphenate the same compound when it follows the noun it modifies: "the interface is well defined."

Do not hyphenate a compound modifier whose first word is an -ly adverb: "a poorly documented API," not "a poorly-documented API." The adverb can only modify the adjective that follows it, so the hyphen adds nothing.

Do not hyphenate a unit of measure written with a numeral: "32 MB," "10 ms," not "32-MB" or "10-ms," even when the pair is being used as a modifier ("a 32 MB heap").

Exclamation and question marks

Do not use exclamation marks in technical documentation. They read as an attempt to manufacture urgency or enthusiasm the content itself does not carry — the same failure mode as the promotional language covered in Promotional language. State the fact plainly instead.

Use a question mark only for a genuine question directed at the reader, such as a heading phrased as a question in a FAQ. Do not use a rhetorical question as a stylistic device to introduce a topic ("But what does this mean for performance?"); state the point directly instead.

Sentences and paragraphs

Prefer simple sentences that express one idea each. Avoid joining two independent clauses with a hyphen, colon, or semicolon when they could instead be split into two separate sentences. A reader has to hold a joined clause in working memory until they reach the end of it before they can parse the meaning of either half. Two short sentences let the reader process and discard each idea in turn.

For example, prefer:

The cache is invalidated on write. This keeps reads consistent with the latest data.

over:

The cache is invalidated on write - this keeps reads consistent with the latest data.

Punctuation-joined clauses are still appropriate where the clauses are genuinely one thought, such as a sentence ending with a short, comma-separated list set off by a colon, or where splitting the sentence would lose an explicit cause-and-effect or contrast that the punctuation itself is signaling. Use judgment. The rule is a default, not an absolute prohibition.

Vary sentence and paragraph length to create pace. A run of uniformly medium-length sentences reads as monotonous, and a run of uniformly short sentences reads as curt. Follow a longer, more detailed sentence with a short one that lands the point. Like this. See? Varies sentence length like this creates a sense of flow and pace.

Similarly, alternate longer paragraphs that develop or qualify an idea with shorter paragraphs, or single-sentence paragraphs, that state a conclusion or transition plainly. Short paragraphs land points, longer ones carry the detail and connective reasoning between them.

A sentence fragment is acceptable as a deliberate device for pace or emphasis, landing a short point after a longer sentence has built up to it: "The request failed. Again." Do not use a fragment where the reader could mistake it for an incomplete sentence rather than a stylistic choice — reserve it for a clause that plainly could not be read any other way.

"That" and "which"

Use "that" to introduce a restrictive clause — one that narrows down which thing is meant, and that the sentence would change meaning without: "the endpoint that returns paginated results." Use "which" to introduce a non-restrictive clause — one that adds incidental information the sentence would still make sense without — set off by a comma: "the endpoint, which was added in v2, returns paginated results." Dropping a restrictive "that" clause changes which endpoint is meant; dropping a non-restrictive "which" clause only removes a side note.

Collective nouns

Treat a collective noun such as "team," "committee," or "data" as singular when it refers to the group as one unit, and as plural only when the sentence is explicitly about the group’s individual members: "the team is responsible for the migration," not "the team are responsible." Treat "data" as singular in technical writing ("the data is inconsistent"), matching common software usage, even though some style guides still require the Latin plural. Do not switch a collective noun’s number partway through a document.

Overused words

Cut a word that adds no meaning to the sentence it sits in — "very," "actually," "basically," "simply," "just," "quite," "really," "so," "in particular," "obviously." Test a candidate by removing it: if the sentence’s meaning is unchanged, the word was padding. This is a general editing discipline, distinct from the LLM-associated vocabulary covered in Overused vocabulary, though the two overlap in practice.

Instructional steps

Sequence a procedure chronologically, not spatially. Prefer "next, select Save to continue" over "click the Save button below": a spatial reference such as "below," "above," "on the left" assumes a fixed visual layout that a screen-reader user, a voice-interface user, or a reader on a narrow viewport does not share, where content is not read or laid out in the same order it appears to a sighted mouse user. A step written as a position in a sequence ("next," "then," "finally") holds regardless of how the interface is rendered or navigated.

Prefer a device-agnostic action verb over a device-specific one: "select" or "choose" over "click," "tap," or "press"; "view" over "see." A device-specific verb assumes the reader is using a mouse, which excludes keyboard, touch, and assistive-technology interaction, none of which is a "click."

AI writing tells

Text drafted or assisted by an LLM tends toward certain patterns that a human editor should recognize and remove. These patterns are not wrong grammatically, but they read as generic, evasive, or hollow, and they erode a reader’s trust once recognized. Treat this section as a checklist to apply during editing, not a rule to write to at first draft.

Inflated significance

Avoid language that asserts importance rather than demonstrating it: "stands as a testament to," "marks a pivotal moment," "underscores the importance of," "plays a crucial role." State what happened and let the reader judge its significance.

Bad: "The migration marks a pivotal moment in the platform’s evolution."

Good: "The migration removes the last dependency on the legacy queue."

Vague attribution

Avoid crediting claims to unnamed authorities: "industry reports suggest," "experts argue," "some critics believe." If a claim needs a source, name it. If it does not, state the claim directly.

Formulaic "challenges" framing

Avoid the reflexive despite-challenges structure ("Despite these challenges, the project continues to…") and generic closing sections such as "Future outlook" or "Challenges and legacy." These add length without adding information. State specific problems and specific plans, or omit the section.

Hollow "-ing" clauses

Avoid trailing participial clauses that restate the sentence’s point in vaguer terms: "…, ensuring reliability," "…, highlighting its flexibility," "…, reflecting the team’s commitment." If the clause is not adding a new, concrete fact, cut it.

Promotional language

Avoid marketing-register words in technical writing: "boasts," "vibrant," "cutting-edge," "seamless," "robust" used as a filler compliment, "in the heart of," "nestled." Technical documentation states facts; it does not sell.

Unearned superlatives and buzzwords are the same problem in a different guise: "revolutionary," "game-changing," "next-generation," "best-in-class," "state-of-the-art," "powerful," "intuitive," "elegant." If a claim like this is true, replace it with the specific, verifiable fact that makes it true. If no such fact exists, delete the claim.

Bad: "A powerful, intuitive API for managing subscriptions."

Good: "An API for managing subscriptions, with one call per lifecycle event."

Vague benefits

Avoid stating a benefit without the specific mechanism or measurement behind it: "enhanced productivity," "improved workflow," "streamlined process," "optimized performance," "increased efficiency." For each, ask what the underlying fact is – faster at what task, by how much, which steps were removed – and state that instead.

Bad: "The new indexer delivers optimized performance."

Good: "The new indexer cuts cold-start query time from 4s to 300ms."

Information priority

Lead with the fact the reader needs, not the buildup to it. State what changed, what is now possible, or how something works in the first sentence. Save background, rationale, or philosophy for after the load-bearing fact, not before it.

Bad: "We’ve been listening to user feedback, and after months of work, we’re pleased to share a new caching layer."

Good: "Responses are now cached for 5 minutes. This removes the need for clients to implement their own caching."

Overused vocabulary

Certain words are disproportionately common in LLM output and read as a tell when they appear often: "delve," "crucial," "leverage," "foster," "landscape" (used abstractly), "tapestry," "testament," "underscore" (as a verb), "robust," "seamless," "intricate." None is forbidden outright, but if a document leans on several of these, rewrite with plainer words.

Copula avoidance

Avoid replacing a plain "is/are/has" with an inflated verb: "serves as," "stands as," "represents a," "boasts a," "features a." Say what a thing is directly.

Bad: "The gateway serves as the entry point for all inbound traffic."

Good: "The gateway is the entry point for all inbound traffic."

Negative parallelism and rule-of-three padding

Avoid "not only… but…" and "it’s not just X, it’s Y" constructions used for rhetorical effect rather than genuine contrast. Avoid padding sentences and lists to a rhetorical three items when two would say it, or four are true.

False ranges

Avoid "from X to Y" constructions where X and Y are not points on a real scale, used only to suggest breadth. "From onboarding to offboarding" is fine if the document actually spans that range end to end; "from data structures to the mysteries of the universe" is padding.

Chatbot artifacts and sycophancy

Technical documentation is not a chat transcript. Do not include conversational framing left over from drafting: "Great question," "Certainly!," "I hope this helps," "Let me know if you’d like me to expand on this," "You’re absolutely right that." Delete these on review; they should never reach a published document.

Knowledge-cutoff hedges

Avoid disclaiming uncertainty in vague terms: "as of my last update," "details are limited," "based on available information." If a fact is uncertain, state what is actually known and its source, or state plainly that it is not yet known.

Filler phrases and hedging

Cut filler that adds words without adding meaning: "in order to" → "to"; "due to the fact that" → "because"; "at this point in time" → "now"; "it is important to note that" → delete; "has the ability to" → "can."

Avoid stacked hedges that dilute a claim past usefulness: "could potentially possibly," "it might be argued that." State the claim with the confidence it actually deserves, once.

Generic positive conclusions

Avoid closing a section with an unearned, content-free upbeat statement: "the future looks bright," "exciting times lie ahead." End on the last concrete fact or the actual next step instead.

Uniform rhythm

Text where every sentence is close to the same length, and every paragraph the same shape, reads as mechanically generated even when each sentence is individually correct.

Stacked em dashes and bold

Overusing em dashes for parenthetical asides, or bolding many phrases within running prose, are also common tells.

Colon and semicolon overuse

Overused colons and semicolons are a common AI writing smell. Almost any sentence built around a semicolon can be split into two plain sentences, and a colon should only ever appear within a sentence that ends with a short, comma-separated list — never to introduce a block list, a code block, or an explainer clause. See Colons for the full rules and examples.

Review pass

After drafting, re-read the text and ask: what here would make a reader suspect this was written by an LLM rather than edited by a person? Revise anything that stands out, and prefer edits that add a concrete detail over edits that simply delete a flagged word.

Glossary

An A-Z reference of individual words, names, and short phrases: preferred spellings, capitalization, and usage notes for terms that come up often enough in prose to be worth a fixed ruling, so a writer does not have to re-decide the same word every time it appears. This section is a word-level companion to the sentence- and paragraph-level guidance elsewhere in this standard, not a restatement of it.

Where an entry conflicts with American spelling conventions used elsewhere in technical writing (color, organize), prefer American spelling in technical documentation per the standard’s general American-English default, unless the entry says otherwise.

Commonly confused words

Word pairs that are spelled differently, sometimes sound alike, and are common wrong-word errors in prose:

accept, except: "Accept" is to receive something, or to give admittance or approval to. "Except," from "exception," means the exclusion of something.
affect, effect: "Affect" (transitive verb) means to influence something so as to bring about a response; the result of that is the "effect" (noun).
biannual, biennial: Use "twice-yearly" and "two-yearly" instead, to avoid confusion.
bogey, bogie: "Bogey" is golf, or a ghost. "Bogie" is a trolley or truck.
canon, cannon: A "canon" is a cleric, a decree, a principle, a body of writings, or a type of music; you fire a "cannon."
canvas, canvass: "Canvas" is the fabric (a tent, a painting); "canvass" is to solicit votes.
caster, castor: "Caster" sugar; "castor" oil.
censor, censure: "To censor" is to prevent publication; "to censure" is to criticize severely.
chard, charred: "Chard" is a salad leaf related to beetroot; "charred" means burnt.
check, cheque: "Cheque" is used to pay for something; "check" covers every other sense.
chord, cord: "Chord" is musical; "cord" is a vocal cord, or rope.
desert, dessert: "Desert" (short "e") is the arid landscape; "dessert" is the sweet food course.
discrete, discreet: "Discrete" means separate and distinct; "discreet" means prudent, showing good judgment about what to reveal.
elicit, illicit: "Elicit" means to draw out or arouse; "illicit" means contrary to accepted morality or law.
elusive, illusive: "Elusive" means difficult to describe or capture; "illusive" means appearing like an illusion.
larva, lava: "Larva" (plural "larvae") is the stage between an egg and an adult insect; "lava" is molten rock from a volcano.
principal, principle: "Principal" is an amount (of money), or the most senior person; "principle" is a truth or a rule.

A

a, an: Use "an" if the "h" is silent: "an hour," "an heir," "an honourable man," "an honest woman"; but "a hero," "a hotel," "a historian."
abbeys: Capitalize: "Westminster Abbey."
Aborigines, Aboriginal: Capitalize when referring to native Australians, lowercase when referring to indigenous populations in general.
about: Preferred to "approximately" in casual use; see also "approximately."
abscess: No usage note.
abysmal: No usage note.
abyss: No usage note.
accommodate, accommodation: No usage note.
achilles heel, achilles tendon: Not "Achilles."
acknowledgment: Not "acknowledgement."
actor: Male and female. Avoid "actress" except in the name of an award, eg "Oscar for best actress."
AD, BC: No usage note.
adaptation: Not "adaption."
addresses: In this format: "1 Queen Square, Bath, BA1 2HN." Keep as short as possible, so avoid including counties unless absolutely necessary.
adrenaline: A hormone that increases heart rate and blood pressure. "Adrenalin" is a trademark.
aeroplane: Not "airplane."
affect, effect: These are not homophones. "Affect" (verb) is to influence something. "Effect" (noun) is the result of a change; "effect" (verb) means to bring something about. See also Commonly confused words.
affinity: "With" or "between," not "to" or "for."
aficionado: Plural: "aficionados."
African-Caribbean: Not "Afro-Caribbean."
ageing: No usage note.
ages: "Tony Blair, 51," not "aged 51." "Little Johnny, four." "The woman was in her 20s." But "twentysomething," "fortysomething."
aggravate: To make worse, not to annoy.
ahead of: Avoid; use "before" or "in advance of."
airbase, aircrew, airdrop, airlift, airmail, aircraft carrier: But "air raid," "air strike."
alibi: Being somewhere else; not synonymous with "excuse."
A-list, B-list: Cliched way to refer to celebrities; avoid.
Allah: Arabic for "the God" (al-Lah). Both "God" and "Allah" refer to the same concept; there is no major difference between God in the Old Testament and Allah in Islam. It therefore makes sense to use "God" in a general or Christian context and "Allah" in quotations from, or in the context of, Islam.
allot, allotted: No usage note.
all right: Correct. "Alright" is not.
al-Qaida: No usage note.
AltaVista: No usage note.
alternative: Strictly, a choice between two courses of action; where there are more than two, "option" or "choice" may be preferred.
Americanisms: Avoid Americanisms and American spellings in a British-style document: "additionally" → "and"; "automobile" → "car"; "anymore" → "any more"; "color" → "colour" (but "discolour," "discoloration"); "corporation" → "company"; "courtroom" spelled as such (not "courtoom"); "customize" → "customise"; "digitize" → "digitise"; "fatality" → "death"; "figure out" → "work out"; cars are "hired," not "rented"; "military" → prefer "the army"; "program" is for computers, "programme" for everything else; children are "brought up," not "raised" (cattle and pigs are "raised"); "regular" is not a synonym for "ordinary" or "normal"; "tad" → "a bit"; "train station" → "railway station"; "transportation" → "transport." This is a British-style convention; this standard’s own default is American spelling — see the section introduction.
America’s Cup: No usage note.
Amhrán na bhFiann: The Irish national anthem.
amid: Not "amidst." Also prefer "among" to "amongst," "while" to "whilst," and so on.
amok: Not "amuck."
among: Not "amongst."
among or between: "Between" is not limited to two parties; it is appropriate when the relationship is essentially reciprocal: "disagreements between the many shareholders." "Among" belongs to distributive relationships: "shared among."
ampersand (&): Use in a company name when the company does: "Marks & Spencer," "P&O." Otherwise, do not use it.
analog: For computing and data; "analogue" for sound.
antenna: "Antenna" (insect), plural "antennae"; "antenna" (radio), plural "antennas."
anticlimax: No usage note.
antihero: No usage note.
antisocial: No usage note.
any more: Not "anymore" (US usage).
apostrophes: Some plural nouns have no "s," eg "children"; these take an apostrophe and "s" in the possessive, eg "children’s games," "gentlemen’s outfitter." The possessive of a word or name ending in "s" normally takes an apostrophe followed by a second "s" ("Jones’s," "James’s"), but be guided by pronunciation and use only the apostrophe where that reads better: "Mephistopheles'" rather than "Mephistopheles’s." Use an apostrophe in a phrase such as "in two days' time," "12 years' imprisonment," and "six weeks' holiday," where the time period modifies a noun, but not in "nine months pregnant" or "three weeks old," where the time period is adverbial. If in doubt, test with a singular such as "one day’s time," "one month pregnant." See also Apostrophes.
appal, appalling: No usage note.
apples: Lowercase: "cox’s orange pippin," "golden delicious," "granny smith."
approximately: Never "approx"; prefer "about" in less formal contexts.
aquarium: Plural "aquariums."
Arab, Arabic: "Arab" is both a noun and an adjective, and the preferred adjective when referring to Arab things in general, eg "Arab history." "Arabic" usually refers to the language and literature: "the Arabic press" means newspapers written in Arabic, while "the Arab press" would include newspapers produced by Arabs in other languages.
archbishop: "The Archbishop of Canterbury"; "the Archbishop of Westminster"; or "archbishop(s)" when talking about them generally. Likewise "the Archdeacon of Farrington," or "the archdeacon."
arguably: One of the most overused words in the language. Avoid it. See also Overused words.
armed forces, armed services, the army: "The British army," "the navy," but "Royal Navy," "Royal Air Force" ("RAF" is fine unexpanded).
around: Do not use when you mean "about," eg "about £1m" or "about 2,000 people."
artefact: No usage note.
artist: Never "artiste."
art movements: Usually lowercase: "art deco," "art nouveau," "cubism," "dadaism," "gothic," "impressionism," "pop art," "surrealism." Exceptions: "Bauhaus," "Modern," "pre-Raphaelite," "Romantic."
the Arts Council: No usage note.
aspirin: No usage note.
assure: See "ensure, insure, assure."
autumn: No usage note.
avant garde: No hyphen.
awards, prizes, medals: Generally lowercase, eg "the Friday at 5 restaurant awards," "Nobel peace prize." Two exceptions: "the Academy Awards," "Victoria Cross." Award categories are also lowercase: "best actor Oscar."
awe-inspiring: Overused, and rarely apt; avoid. See also [Overused words].
Ayers Rock: See "placenames."

B

BC AD: No usage note.
Babybel: Cheese.
back-end: Adjective and noun; "back end" is the verb.
backstreet: No usage note.
backward compatible: Not "backwards."
backwoodsman: No usage note.
Band-Aid: Trademark; say "plaster" or "sticking plaster."
band names: Lowercase "the": "the Beatles," "the Black Eyed Peas."
B&B: Acceptable abbreviation for "bed and breakfast."
bank holiday: No usage note.
banknote: No usage note.
barbecue: No usage note.
Barclays Bank: No usage note.
Barnardo’s: Children’s charity, formerly "Dr Barnardo’s"; it no longer runs orphanages.
barolo: Wine.
baroque: No usage note.
bas-relief: A method of sculpting which entails carving or etching away the surface of a flat piece of stone or metal.
battlebus: No usage note.
Bauhaus: No usage note.
BBC1, BBC2, BBC3, BBC4: No spaces.
BBC6 Music: "6 Music" on second mention.
BC: See "dates."
beau: Plural "beaux."
befitted: No usage note.
begs the question: Often misused: it means assuming a proposition that, in reality, involves the conclusion — for example, it begs the question to say that parallel lines will never meet because they are parallel. It does not mean "raises the question."
believable: No usage note.
Bell’s: Whisky.
bellwether: The sheep that leads the herd; customarily misspelt, misused, or both.
benefited, benefiting: No usage note.
beta: No usage note.
betting odds: These are meaningless to many readers, so avoid mentioning them without explanation. Long odds (eg "100-1 against," normally expressed as "100-1") mean something unlikely; shorter odds (eg "10-1") still mean it’s unlikely, but less so; "odds on" (eg "2-1 on," sometimes expressed as "1-2") means it is likely — a £2 bet would win only £1 plus the stake.
biannual, biennial: Best avoided. "Biannual" means twice a year, "biennial" means every two years; use "twice-yearly" or "two-yearly" instead, since readers may not know the difference either. See also Commonly confused words.
bias, biased: No usage note.
Bible: Capitalize when referring to the Old or New Testament; lowercase in a sentence such as "the style guide is my bible."
biblical references: "Genesis 1:1," "II Corinthians 2:13," "Revelation 3:16" — not "Revelations."
bicentenary: A 200th anniversary; "bicentennial" is its adjective.
bid: Use only in a financial sense, such as for auctions.
big: Usually preferable to "major," "massive," "giant," "mammoth," "behemoth."
billion: See "numbers."
Birds Eye: Trademark; no apostrophe.
birdwatchers: Also known as "birders," but never "twitchers."
birdwatching: Or "birding," not "twitching."
Biro: Trademark; say "ballpoint pen."
birthplace, birthrate, birthright: No usage note.
bishops: "The Right Rev Clifford Richard, Bishop of Wimbledon," at first mention; thereafter "the bishop" or "Bishop Richard."
bite-size: Not "bite-sized."
black: Lowercase as noun and adjective when referring to race.
Black Country: No usage note.
black-and-white: Adjective, but the noun is "black and white" (eg "he saw things in black and white").
blackout: No usage note.
blase: No accent, despite the way it is pronounced.
blitz, blitzkrieg: No usage note.
blond, blonde: "Blond" is the adjective and the male noun; "blonde" is the female noun.
Bloody Sunday: No usage note.
Bluffer’s Guide: Trademark; avoid using.
Blu-Tack: Trademark.
blue chip: No usage note.
the Boat Race: No usage note.
bogey, bogie: See Commonly confused words.
bona fide, bona fides: No usage note.
bookcase, bookkeeper, bookseller, bookshelf: No usage note.
book and film titles: Initial caps for the first word of a title, and all other words except "a," "an," "and," "of," "on," "the": "A Tale of Two Cities," "The Pride and the Passion."
bon vivant: Not "bon viveur."
bored with, bored by: Not "bored of."
both: Unnecessary in most sentences that already contain "and"; "both men and women" says no more than "men and women."
bottleneck: No usage note.
bourgeois: Adjective; "bourgeoisie" is the noun.
box office: No usage note.
boy: Male under 18.
boyfriend: No usage note.
boy’s own: No usage note.
brackets: See "parentheses."
braille: No usage note.
Brands Hatch: No apostrophe.
bric-a-brac: No usage note.
brickbat: Cliche; avoid.
Britain, UK: These terms are synonymous: "Britain" is the official short form of "United Kingdom of Great Britain and Northern Ireland." Used as adjectives, "British" and "UK" mean the same. "Great Britain," however, refers only to England, Wales, and Scotland — take care not to write "Britain" when only England and Wales are meant.
Britart: No usage note.
the British Council: No usage note.
the British Film Institute: "BFI" on second mention.
the British Library: No usage note.
the British Museum: No usage note.
Britpop: No usage note.
Britvic: Trademark.
brownie points: No usage note.
Brum, Brummie: No usage note.
brussels sprouts: No usage note.
Brylcreem: Trademark.
BST: British Summer Time; no need to spell it out.
Buckingham Palace: "The palace" on second mention.
bugbear: Overused in reviews; avoid.
bulletproof: No usage note.
Burberry: Trademark.
bureau: Plural "bureaus" (furniture) or "bureaux" (organizations).
burned, burnt: "Burned" is the past tense form ("he burned the cakes"); "burnt" is the participle, a more adjectival form of the verb ("the cakes are burnt").
buses, bussed, bussing: No usage note.
businesslike, businessman, businesswoman: No usage note.
businessmen: Prefer "business people" or "the business community."
but, however: Often redundant, and increasingly used to connect two compatible statements; "in contrast, however…" is tautologous. See also Overused words.
Butlins: But "Pontin’s."
butterflies: Lowercase: "painted lady," "red admiral."
buy: Prefer "buy" to "purchase" as a verb; "purchase" is fine as a noun.
buyout: But "buy-in."
byelection, bylaw, bypass, bystander: No usage note.

C

cabin attendant, flight attendant, cabin crew, cabin staff: Not "air hostess," "air stewardess."
Caesars Palace: No apostrophe.
cafe: No acute accent.
call centre: No usage note.
Calor: Trademark; prefer "camping gas."
Campari: Trademark.
canon, cannon: See Commonly confused words.
canvas, canvass: See Commonly confused words.
capital letters: Initial caps for the names of artistic and cultural institutions ("British Museum," "Tate Modern"). For churches, hospitals, and schools, capitalize the proper or place name and lowercase the rest ("Great Ormond Street children’s hospital," "St Peter’s church"). For universities and colleges, capitalize the institution and lowercase the department ("Sheffield University department of medieval and modern history"). Geographical features and bridges are always lowercase ("river Thames," "the Wash," "Golden Gate bridge," but "Mount Everest"). Words based on proper names that have lost their connection to the origin ("alsatian," "cardigan," "champagne," "french windows") are usually lowercase. Job titles are all lowercase ("prime minister," "US secretary of state"); differentiate a title from a job description ("President Bush," but "the US president, George Bush," and "Mr Bush" on later mention). British government departments and agencies take initial capitals only when citing the actual title ("Home Office," "Foreign Office," but "foreign ministry"). Acts of Parliament take initial caps; bills do not, until enacted ("the criminal justice bill" becomes "the Criminal Justice Act").
cappuccino: No usage note.
cards: "Scratchcard," "smartcard," "swipecard," but "credit card," "debit card."
career girl, career woman: Avoid; outdated and has no male equivalent.
cashmere: Fabric. "Kashmir" is a place.
castoff: One word (noun and adjective); "cast off" (two words) is the verb.
catchphrase: No usage note.
catch-22: Lowercase unless specifically referring to Joseph Heller’s novel "Catch-22."
cathedrals: Capitalize: "Canterbury Cathedral."
the Catholic church: No usage note.
CD, CDs, CD-Rom, CD-R, CD-RW: No usage note.
celsius, centigrade: See "temperatures."
Celtic: Not "Glasgow Celtic."
censor, censure: See Commonly confused words.
Center Parcs: No usage note.
centre: "On" or "in"; "revolve around."
centuries: See "dates."
chair: Acceptable in place of "chairman" or "chairwoman."
Channel 4, Channel Five: But "Five" at second mention.
Channel tunnel: Never "Chunnel."
chardonnay: Lowercase, like other wines, whether named after a grape or a region.
chateau, chateaux: No usage note.
Chatham House rule: Often mistakenly called "rules" — there is just one: "When a meeting, or part thereof, is held under the Chatham House rule, participants are free to use the information received, but neither the identity nor the affiliation of the speaker(s), nor that of any other participant, may be revealed." Chatham House is more formally the Royal Institute of International Affairs, based at Chatham House in London.
chatroom: No usage note.
chatshow: And "talkshow," "gameshow."
checkout: Noun and adjective; "check out" is the verb.
check, cheque: See Commonly confused words.
chief constable: A job, not a title: "John Smith, chief constable of Greater Manchester."
childcare: No usage note.
childminder: No usage note.
chitchat: No usage note.
chock-a-block: No usage note.
choose: "Chose" is the past tense.
chord, cord: See Commonly confused words.
christened, christening: Use only for a Christian baptism.
Christian, Christianity: But "unchristian."
Christian name: Write "first name" or "forename" instead.
Christian Union: An evangelical Christian organization.
Christie’s: No usage note.
Christmas Day, Christmas Eve: No usage note.
chronic: Means lasting for a long time or constantly recurring; often misused when "acute" (short but severe) is meant. See also [Commonly confused words].
church: Lowercase for the established church in general ("the church is no longer relevant today"); "Catholic church," "Anglican church," but "Church of England."
cineaste: Someone who enjoys films; in French, a "cinéaste" is someone who makes them. Prefer "cinemagoer."
city: In Britain, a town that has been granted a charter by the crown; it usually has a cathedral.
City: Capitalize when used as shorthand for the City of London.
classical music: "Mozart’s 41st Symphony (or Symphony No 41) in C, K551"; "Rachmaninov’s Piano Concerto No 2"; "Schubert’s Sonata in A minor for Piano, D845."
clearcut: No usage note.
codename: No usage note.
cliches: Avoid cliches. Common examples: "back burner," "ball in your court," "bouquets and brickbats," "changing hands," "dog eat dog," "drop-dead gorgeous," "fly by night," "hands on/off," "go over your head," "in the black," "you scratch my back I’ll scratch yours," "sweet sorrow," "talk shop," "time is money."
cliffhanger: No usage note.
climbdown: Noun; "climb down" is the verb.
cloud cuckoo land: No usage note.
coalfield, coalmine, coalminer: No usage note.
Coalite: Trademark.
coarse fishing: No usage note.
coastguard: No usage note.
Coca-Cola, Coke: Trademarks.
cockney: No usage note.
coconut: No usage note.
cold war: No usage note.
collective nouns: See Collective nouns.
College of Arms: No usage note.
colleges: Take initial caps, eg "Fire Service College," but not when "college" forms part of the name of a school.
colloquialisms and slang: Avoid colloquialisms and slang generally.
colons: See Colons.
colonel: "Colonel Napoleon Bogey," subsequently "Col Bogey."
comedian: Male and female; do not use "comedienne."
commas: See Commas. Note also that "the subeditor, John Doe, is an expert on style" implies there is only one subeditor, while "the subeditor John Doe is an expert on style" (no commas) implies there is more than one.
commented: Avoid; prefer "said."
Commons, House of Commons: No usage note.
common sense, common-sense: "Common sense" (noun), "common-sense" (adjective).
Commonwealth, the: No usage note.
communique: No accent.
company names: Companies are singular: "Macromedia has dropped…," not "Macromedia have dropped…" Do not adopt a company’s own typographic logo styling (all caps, unusual casing) where it is not itself an abbreviation. See also Collective nouns.
compare to, compare with: "Compare to" means "liken to"; "compare with" means "make a comparison." Use "compare with" unless deliberately likening one thing to another.
compass points: Lowercase for regions: "the north," "the south-west," "north-east England"; the same applies to geopolitical areas: "the west," "western Europe," "the far east," "south-east Asia," "central America." Capitalize when part of the name of a county ("West Sussex," "East Riding of Yorkshire") or province ("East Java," "North Sulawesi"). Note: "East End," "West End" (London), "West Country," "Middle East," "Latin America," "North America."
complement, compliment, complimentary: "To complement" is to make complete; "to compliment" is to praise; "complimentary" as in "a complimentary copy" means free. See also Commonly confused words.
complete: Prefer to "finalise."
comprise: To consist of; "comprise of" is wrong. See also [Commonly confused words].
Congregational: Uppercase when referring to the Congregational Union of England and Wales, formed in 1832, which joined the Presbyterian Church of England in 1972 to form the United Reformed church.
conjoined twins: Not "Siamese twins."
Conservative party: No usage note.
consult: Not "consult with."
contemporary: Of the same period, though often wrongly used to mean "modern"; a performance of Shakespeare in contemporary dress would involve Elizabethan costume, not 21st-century clothes.
the continent: Mainland Europe.
continual: Refers to things that happen repeatedly but not constantly; "continuous" indicates an unbroken sequence. See also [Commonly confused words].
contractions: See Abbreviations and acronyms.
conversions: See "measurements and quantities."
convince, persuade: Having convinced someone of the facts, you might persuade them to do something. See also Commonly confused words.
cooperate, cooperation, cooperative: No hyphen, but "the Co-op" (store).
coordinate: Not "co-ordinate."
cord, chord: See Commonly confused words.
corporation of London: No usage note.
corps de ballet: No usage note.
cortege: No accent.
councils: Lowercase apart from the place name: "Rochester upon Medway council," "London borough of Southwark," "Kent county council."
counter-attack: No usage note.
coupe: No accent.
courts: All lowercase: "court of appeal," "high court," "supreme court," "magistrates court" (no apostrophe), "European court of human rights," "international criminal court."
court martial: Plural "courts martial."
crescendo: A gradual increase in loudness or intensity; musically or figuratively, it is the build-up to a climax, not the climax itself.
cricket terms: "Leg-side," "leg-spinner," "off-spin," "off-stump," "silly mid-on," "mid-off."
criterion: Plural "criteria."
Crombie: Trademark.
the crown, crown estate, crown jewels: No usage note.
the crucifixion: No usage note.
Crufts: No usage note.
the Crusades: No usage note.
cubism, cubist: No usage note.
cul de sac: No usage note.
cumberland sausage: No usage note.
curb, kerb: "To curb" is to restrain; a "kerb" is part of a pavement. See also Commonly confused words.
currencies: The whole word is lowercase: "euro," "pound," "sterling," "dong." Abbreviate: "$50" (US dollars), "A$50" (Australian dollars), "HK$50" (Hong Kong dollars), "€40.00" (euros). Convert a foreign amount to a familiar currency in brackets at first mention.
currently: Usually redundant. If used, prefer "now." See also [Overused words].
cusp: A place where two points meet; sometimes misused to mean "on the brink."
customise: Not "customize" (US spelling). See also "Americanisms."
cutbacks: "Cuts" will suffice.
cut-throat: No usage note.
cutting edge: Noun; "cutting-edge" is the adjective.
cyberspace: No usage note.
Czech Republic: No usage note.

D

dadaism, dadaist: No usage note.
dancefloor: No usage note.
dangling participles: A dangling (or misplaced) modifier is a word or clause that ambiguously modifies another, possibly confusing the writer’s intended meaning. "Having died, they buried him" attaches "having died" to "they," the subject immediately after the comma — but "they" cannot have died and then buried him. Likewise "when young, circuses appeal to all of us" reads as if the circuses were young, not the audience.
dark ages: No usage note.
dashes: See Dashes.
data: See Collective nouns.
dates: Standard format: "1 January 2000," no commas; or "Monday, 1 January 2000." Write years as "2003," not "the year 2003." For a span of years, "1995-99," or "between 1995 and 1999," not "between 1995-99." Centuries are spelled out ("sixth century," "eleventh century") except "20th century" and "21st century." "AD2006" but "1000BC" — AD goes before the date, BC goes after; both go after a century ("second century AD," "fourth century BC"). For decades use figures: "the swinging 60s" or "1960s"; "mid-60s," "mid-90s." See also Numbers, dates, and units.
daylong: But "month-long," "year-long."
day-to-day: No usage note.
D-day: No usage note.
debacle: No accents.
debatable: No usage note.
decades: See "dates."
defensible: No usage note.
defuse, diffuse: "Defuse" is to render harmless; "diffuse" is to spread about. See also Commonly confused words.
deja vu: No accents.
delusion, illusion, allusion: "Allusion" is a casual or subtle reference. "Delusion" is a mistaken conviction about reality resulting from impaired or misleading judgment. "Illusion" is a fanciful or unreal occurrence. See also Commonly confused words.
dependant, dependent: "Dependant" (noun); "dependent" (adjective).
dependence: No usage note.
depositary, depository: "Depositary" is a person; "depository" is a place.
the Depression: No usage note.
de rigueur: Avoid using foreign phrases such as this. See also [Foreign words].
dessert, desert: "Dessert" is the sweet course; "desert" (short "e") is the arid landscape. See also Commonly confused words.
developing countries: Prefer "less developed countries" and avoid "third world."
the devil: No usage note.
dialects: "Cockney," "estuary English," "geordie," "scouse."
dialog, dialogue: "Dialog" (box); "dialogue" (speech). See also [Commonly confused words].
dial-up: For internet connections.
Dictaphone: Trademark.
die-hard, die hard: "Die-hard" (noun); "die hard" (verb).
dietician: No usage note.
different from, different to: Not "different than."
digitise: Not "digitize" (US spelling). See also "Americanisms."
disc, disk: "Compact disc," "CD," "DVD." But "hard disk," "floppy disk."
Dinky Toys: Trademark.
disabled people, disabled persons: Not "the disabled." Likewise "blind people," "dead people," "deaf and speech-impaired," "hearing and speech-impaired." Never use "victim of," "crippled by," "suffering from," "afflicted by," "wheelchair bound" (instead, simply "uses a wheelchair"), "invalid," or "mentally handicapped" (instead, "person with learning difficulties") — person-first phrasing names the person before the condition. The same principle extends to gender-neutral language: prefer "humankind" to "mankind," and a gender-neutral construction ("they," or a recast sentence) over "he" or "his" to refer to a person of unspecified gender.
discernible: Not "discernable."
discolour: But "discoloration."
discreet, discrete: "Discreet" means showing prudence; "discrete" means separate. See also Commonly confused words.
disinterested: Means free from bias, objective; it does not mean "uninterested," not taking an interest. See also [Commonly confused words].
disk: See "disc, disk."
dispatch, despatch: Both are technically correct; write "dispatch," "dispatched."
Disprin: Trademark.
Disneyland Paris: Not "Euro Disney."
dissociate, dissociation: Not "disassociate," "disassociation."
distances: Use miles rather than kilometres, but otherwise use metric units (metres in preference to yards). Write "metres" out in full to avoid confusion with "million" (an obvious exception is athletics, eg "she won the 400m").
Dr: No usage note.
Doctor Who: The title of the series, not "Dr Who." The character is "the Doctor."
dogs: Lowercase: "alsatian," "doberman," "rottweiler," "yorkshire terrier"; but "Irish setter," "old English sheepdog."
D’oh!: As Homer Simpson would say.
Dolby: Trademark.
the dome: "Millennium Dome" at first mention, thereafter "the dome."
dos and don’ts: No usage note.
dotcom: Not "dot.com."
downmarket: No usage note.
Down’s syndrome: No usage note.
dozen: Precisely, not "about," 12.
draconian: No usage note.
drag-and-drop: Noun; "drag and drop" is the verb.
dreamed: Not "dreamt."
dressing room: No usage note.
driving licence: Not "driver’s licence."
drop-down: For a computer menu.
drum’n’bass: No usage note.
drunkenness: No usage note.
dub: Avoid tabloid phrasing such as "dubbed the next big thing."
due to, owing to: "It was difficult to assess the changes due to outside factors" says the changes were a result of outside factors; "it was difficult to assess the changes owing to outside factors" says outside factors made the assessment itself difficult. If in doubt, substitute "because of" — it works for either meaning, unlike "due to."

E

exposé: No usage note.
earlier: Often redundant, since context informs the reader: "this month" is usually preferable to "earlier this month." See also Overused words.
earshot: No usage note.
Earth: But "moon," "sun." Lowercase "earth" when referring to soil, the ground.
east coast mainline: No usage note.
EastEnders: No usage note.
Easter Day: Not "Easter Sunday."
easyJet: No usage note.
eBay: No usage note.
ebook: No usage note.
eccles cake: Lowercase, even though it comes from Eccles, Lancashire.
ecommerce: No usage note.
ecstasy: No usage note.
Edinburgh festival, Edinburgh Fringe festival: No usage note.
effect, affect: See "affect, effect."
effectively: Overused as well as misused; it is not a synonym for "in effect." See also Overused words.
eg: No full points, and no comma after it: "eg like this." See also Abbreviations and acronyms.
elbowroom: No usage note.
elite: No accent.
ellipsis (…): An ellipsis at the end of a sentence needs no additional full stop: "like this…"
email: No usage note.
embarrass, embarrassment: No usage note.
embassy: Lowercase, eg "British embassy."
enable: Nothing wrong with this word, but in most cases "allow" is shorter and reads more plainly.
enamoured of: Not "by" or "with."
encyclopedia: "Encyclopaedia" is a correct alternative spelling, but this standard prefers "encyclopedia."
end-user: No usage note.
enforce, enforceable: No usage note.
England: Take care not to write "England" or "English" when "Britain" or "British" is meant.
English Heritage, English Nature, English Partnerships: No usage note.
en masse: No usage note.
enormity: Something monstrous or wicked, not a synonym for "large." See also Commonly confused words.
enrol, enrolling, enrolment: No usage note.
en route: Not "on route."
ensure, insure, assure: "Ensure" is to make certain; "insure" is against risk; "assure" is life (as in life assurance). See also [Commonly confused words].
enthral, enthralling: No usage note.
environment: Means the natural environment. "The office environment" is just "the office."
ere long: Not "e’er long" — and avoid the phrase regardless.
espresso: Not "expresso."
etailer: An online store. Prefer "online shop" or "online retailer."
ethnic: Never say "ethnic" when "ethnic minority" is meant — using "ethnic" alone leads to constructions such as "the constituency has a small ethnic population."
EU: European Union; no need to spell out at first mention.
euro: Currency; plural "euros" and "cents." See "currencies."
Euro Disney: Now called "Disneyland Paris."
Europe: Includes Britain, so avoid saying something is common "in Europe" unless it is common in Britain as well. "Continental Europe" distinguishes Britain from the rest of the continent; also "eastern Europe," "central Europe," "western Europe."
Eurovision song contest: No usage note.
every day, everyday: "Every day" (noun and adverb): "it happens every day." "Everyday" (adjective): "an everyday mistake." See also [Commonly confused words].
every parent’s nightmare: Cliche; avoid.
exclamation marks: See Exclamation and question marks.
expandable: Not "expandible."
expat, expatriate: Not "ex-pat" or "expatriot."
explained: Write "he said," not "he explained."
extraterrestrial: No usage note.
extrovert: No usage note.
eye level: No usage note.
eyewitness: One word, but prefer "witness."

F

facade: No cedilla.
FA Cup: "The Cup" after first mention; other cups are lowercase at second mention.
fahrenheit: See "temperatures."
Fáilte Ireland: Ireland’s tourism authority.
faint-hearted: No usage note.
fairytale: No usage note.
fallout: Noun; "fall out" is the verb.
famous people: "Beyoncé" (formerly "Beyoncé Knowles"); "Salvador Dalí" (note the accent); "Dame Judi Dench," not "Judy"; "Robert De Niro," not "DeNiro"; "Danny DeVito"; "Leonardo DiCaprio"; "Gandhi," not "Ghandi"; "Paul Gauguin," often misspelled "Gaugin"; "Andrew Lloyd Webber."
far, farther, farthest: For distances; otherwise "further," "furthest."
fascism, fascist: No usage note.
fashion weeks: Lowercase, eg "London fashion week."
fatality: Use "death."
father of two: And similar; not "father-of-two."
fed up with: Not "fed up of."
feelgood factor: Cliche; do not use.
fellow artist, fellow members: Do not hyphenate this kind of construction.
ferris wheel: No usage note.
festivals: Lowercase, eg "Cannes film festival," "Edinburgh Fringe festival," "Glastonbury."
fete: No accent.
fewer, less: "Fewer" means smaller in number, eg "fewer coins"; "less" means smaller in quantity, eg "less money." See also [Commonly confused words].
fiance, fiancee: "Fiance" (male), "fiancee" (female); but "divorcee" is both.
figures: See "numbers" and "fractions."
filename: For a computer file.
film titles: See "book and film titles."
filmmaker, filmmaking: No usage note.
Filofax: Trademark. Prefer "personal organiser."
finalise, finalised: Avoid; use "complete," "completed."
fine-tooth comb: No usage note.
fine-tune: No usage note.
firefighter: Not "fireman."
Firefox: The web browser.
first: Spell out "second," "third" through "ninth"; then "10th," "21st," "millionth." Figures may be used in titles and headlines. See also Numbers, dates, and units.
firstly: Write "first," "second," "third."
first aid: No usage note.
first-hand: No usage note.
first name: Not "Christian name" or "forename."
first world war: No usage note.
flak: Not "flack."
flash-drive: No usage note.
flaunt, flout: "To flaunt" is to make a display of something, as in flaunting wealth; "to flout" is to show disregard for something, as in flouting the seatbelt law. See also Commonly confused words.
flexitime: No usage note.
flounder, founder: "To flounder" is to perform a task badly; "to founder" is to fail — a business might founder because its leaders are floundering. See also Commonly confused words.
flu: No usage note.
fluky: Not "flukey."
flyer: Not "flier."
fogey: Not "fogy."
following: Prefer "after," eg "Mansfield Town went to pieces after their Cup exit."
foot and mouth disease: No usage note.
forbear, forebear: "Forbear" means to abstain; "forebear" means an ancestor. See also Commonly confused words.
foreign words and phrases: Never use a foreign word where a suitable English equivalent exists. Where one genuinely must be used, a foreign word commonly used in English generally takes no accent — the standard’s exception is "exposé." See Foreign words for this standard’s own italicization rule, which differs from a house style that sets no foreign word in italics at all.
forego, forgo: "Forego" means go before; "forgo" means go without.
forever, for ever: "Forever" means continually: "he is forever changing his mind." "For ever" means for always: "I will love you for ever." See also Commonly confused words.
forgivable: No usage note.
formula one: For motor racing; not "Formula One" or "F1."
fortuitous: By chance, accidental; not "by good fortune, lucky." See also Commonly confused words.
Fourth of July: American Independence Day.
foxhunting: No usage note.
fractions: "Two-thirds," "three-quarters." But "two and a half." See also Numbers, dates, and units.
Frankenstein: The monster’s creator, not the monster.
freeform: No usage note.
french kiss, french leave, french letter, french polish, french window: Lowercase "french" in these set phrases.
fresco: Plural "frescoes."
freudian slip: No usage note.
Friends of the Earth: Abbreviate to "FoE" after first mention.
fuel: Overused as a verb. See also Overused words.
fulsome: Means "cloying, excessive, disgusting by excess." It is not a more elaborate word for "full." See also Commonly confused words.
fundraiser, fundraising: No usage note.
future-proof: No usage note.

Food and drink terms

A supplementary A-Z of food, drink, and culinary terms, kept separate from the main glossary above because it is domain vocabulary rather than general-purpose usage guidance — relevant chiefly to documentation that discusses food, catering, or hospitality software.

al dente: A term, meaning "to the bite," used to describe the correct degree of doneness for pasta and vegetables. Avoid using this term as a cliche for "perfect."
alfredo: A pasta sauce originally consisting of butter, cream, and parmesan cheese.
allemande: A sauce made of veloute (usually veal), a liaison, and lemon juice.
angelica: Licorice-flavoured stalks, candied and used in pastry-making; also used to flavour liqueurs.
antipasto: The Italian word for snacks served before a meal — cured meats and salamis, olives, marinated vegetables, cheese.
arrowroot: A starch similar in appearance and qualities to cornstarch.
artichoke: A name shared by three unrelated plants: the globe artichoke, Jerusalem artichoke, and Chinese (or Japanese) artichoke.
aubergine: The French word for eggplant; prefer "aubergine."
Babybel cheese: Note the uppercase brand name.
baekenhofe: An alsacienne stew of pork, lamb, and beef layered with potatoes and onions.
bakewell tart: No usage note.
bangers: British colloquial for sausages; prefer "sausages," though "bangers and mash" is fine as a dish name.
barolo wine: No usage note.
basquaise: Food prepared in the Basque style, often including tomatoes and sweet or hot red peppers.
bearnaise: The most notable of the hollandaise sauce variations.
beef wellington: Beef and mushrooms wrapped in puff pastry.
Bell’s whisky: No usage note.
bete noire: A rich flourless chocolate cake; no accents.
biscotti: Dry Italian cookies flavoured with almonds, chocolate, or anise seed.
bourguignonne: Food cooked in the style of Burgundy — red wine, mushrooms, pearl onions, bacon.
Boddingtons: A beer.
bordeaux: A wine; lowercase.
bran: The outer husk of grains such as wheat.
bruschetta: Garlic bread.
brussels sprouts: Note the lowercase spelling.
calamari: The Italian word for squid.
canape: Small open-faced sandwiches served as snacks; may be called "sandwiches" instead.
cannelloni: An Italian dish of pasta sheets or tubes filled with meat, cheese, or fish.
caper: The pickled bud of the caper bush, used in sauces and as a condiment for smoked fish and niçoise salad.
capicolla: A coarse Italian pork sausage.
capsicum: The family name for sweet and hot peppers.
carbonara: A rich pasta sauce of pancetta, eggs, and parmesan cheese; "carbonara pasta sauce."
carpaccio: An Italian dish of paper-thin beef slices dressed with olive oil and parmesan cheese.
caster sugar: But "castor oil."
caviar: Not "caviare."
chablis: A wine; lowercase.
chai: The Indian name for tea, often served with milk and sugar; call it "Indian tea."
chantilly: Sweetened whipped cream flavoured with vanilla.
chardonnay: See "chardonnay" above.
chapati: A whole wheat Indian flatbread; "chapati bread."
cheddar, cheshire: Cheeses; lowercase.
chicken tikka masala: No usage note.
chutney: A large range of sauces or relishes used in East Indian cooking.
clotted cream: A Devonshire specialty, also known as "Devon cream," but write "clotted cream."
cock-a-leekie: A thick Scottish soup of chicken, leeks, and barley.
cocoa powder: The dried powder formed from chocolate liquor after reducing the cocoa butter content.
coconut milk: Not the liquid found in the centre of a coconut, but a thick liquid made by steeping fresh grated coconut in hot water.
cornish pastry: No usage note.
courgette: The French word for zucchini.
couscous: A pasta made from semolina; also the dish in which semolina or cracked wheat is steamed while meat, vegetables, chickpeas, and raisins simmer beneath.
crackling: Crispy pieces of skin remaining after fat is rendered — pork, duck, or goose.
cream: The portion of milk that rises to the top when the milk has not been homogenized.
creme anglaise: A custard of milk and eggs, used as a dessert sauce or a mousse base.
creme caramel: A baked custard flavoured with caramel, like the Spanish flan.
crepe: A very thin pancake used for sweet and savoury fillings.
croque-monsieur: The French grilled ham and cheese sandwich, made with Gruyere.
croquette: A thick patty of cooked foods.
crostini: Toasted bread slices brushed with olive oil and served with a topping — tomatoes, pumate, cheese, chicken liver mousse, bean puree, or tapenade.
croutons: Bread cut into small pieces and toasted or fried until crisp.
cumberland sauce: An English sauce for ham, game, and pâtés; note the lowercase spelling.
curry powder: A spice mix.
cuttlefish: A cousin to the squid.
dim sum: A selection of small dishes served for snacks and lunch in China.
dover sole: No usage note.
eccles cake: From Eccles, Lancashire.
escalope: A thinly sliced food, similar to a scallopine — meat, fish, or vegetables.
falafel: A Middle Eastern dish of small, deep-fried croquettes of spiced, ground chickpeas, usually served in pita bread.
florentine: Describes food cooked in the style of Florence, most commonly associated with spinach; "steak Florentine" is a T-bone steak with olive oil, garlic, and lemon.
focaccia: An Italian flatbread made with pizza or bread dough, plain or topped.
foie gras: Literally "goose liver," but used for the fattened liver of both duck and geese.
fondue: Several types exist; cheese fondue is the most notable, a Swiss specialty.
fritter: Food dipped in batter and deep-fried or sautéed.
gelato: An Italian frozen dessert made of whole milk and eggs.
goulash: A Hungarian soup or stew of beef, liberally seasoned with paprika.
granola: Toasted grain (oats), dried fruit, and nuts, usually a breakfast cereal.
guacamole: A dip of mashed avocado, onions, tomatoes, chiles, and cilantro.
hollandaise sauce: The most basic of the egg-and-oil emulsified sauces, flavoured with fresh lemon juice.
licorice: No usage note.
kebab: Skewers of meat, fish, or vegetables grilled over a fire.
madeira: A wine and a cake.
marzipan: An almond paste with egg whites, kneaded smooth and used to wrap or layer cakes and candies.
meatloaf: No usage note.
meringue: Whipped egg whites with sugar, forming a stiff paste, used to lighten mousses, cakes, and pastry creams.
mincemeat: A sweet, spicy mixture of candied and fresh fruits, wine, spices, and beef fat.
minestrone: An Italian vegetable soup with beans and pasta or rice.
mousse: A sweet or savoury dish of blended, folded ingredients.
nougat: A candy of sugar and honey mixed with nuts.
nutella: Trademark; a commercial brand of gianduja.
omelette: No usage note.
paella: A Spanish rice dish originating in Valencia; rice, tomatoes, and saffron are the essential ingredients.
pate: A French term for pastes or pastry; write without accents.
peking duck: No usage note.
penne: Quill-shaped pasta tubes with smooth sides.
Pimm’s: No usage note.
pita bread: Flat round bread, with or without a pocket.
poppadom: No usage note.
profiterole: A small puff of pâte à choux, usually filled and served as an appetizer.
quiche: No usage note.
quince: No usage note.
ratatouille: No usage note.
ravioli: No usage note.
risotto: No usage note.
sangria: No usage note.
satay: No usage note.
sea urchin: A round spiny creature found off the coasts of Europe and America; only the coral is eaten, usually raw with lemon juice.
shortbread: One word.
skate wings: The edible portion of the skate.
soy sauce: No usage note.
spring roll: No usage note.
stock: A flavoured broth from meat, fish, shellfish, or vegetables — the basis of sauce- and soup-making.
sweetbread: The culinary term for the thymus gland of an animal.
tagliatelle: No usage note.
tartare: No usage note.
temazepam: No usage note.
tiramisu: No usage note.
toad in the hole: No usage note.
tofu: No usage note.
tortellini: A stuffed pasta of small rounds of dough twisted into dumplings.
tortelloni: The larger version of tortellini.
tortilla: A thin pancake of cornmeal or flour.
tripe: The stomach of beef, pork, or sheep.
truffle: No usage note.
turkish delight: No usage note.
vanilla: A plant native to Mexico, whose pod is used to make culinary extracts.
vinaigrette: A sauce for dressing salads, made of oil and vinegar.
welsh rarebit: Often confused with "Welsh rabbit"; a cheese sauce made with ale and seasoned with dry mustard, black pepper, and Worcestershire sauce, traditionally served over toast.
whisky: Plural "whiskies"; but Irish and US "whiskey."
worcestershire sauce: Lowercase; a condiment of anchovies, tamarind, vinegar, molasses, and cloves.
yeast: A fungus used in the production of bread and beer.
yorkshire pudding: No usage note.

G

gaff, gaffe: "Gaff" is a hook or spar, also slang for a house; "to blow the gaff" is to give away a secret. "Gaffe" is a faux pas. See also Commonly confused words.
gambit: An opening strategy that involves some sacrifice or concession — "opening gambit" is tautologous; "opening ploy" may be better.
gameshow: No usage note.
Garda: The Irish police force; "garda" (plural "gardaí") is an Irish police officer.
gay: Use as an adjective, eg "gay people," rather than a noun ("gays"), though "gays and lesbians" is acceptable.
gender issues: See "disabled people, disabled persons" for this standard’s person-first and gender-neutral phrasing rule, which extends to: "actor," "comedian" (covering men and women; not "actress," "comedienne"), "business person," "firefighter" (not "fireman"), "humankind" (not "mankind"), "PC" (not "WPC"). Avoid "his" to cover men and women generally — recast the sentence instead: "teachers who beat their pupils," not "a teacher who beats his/her pupils."
general election: No usage note.
generally speaking: Avoid. See also Overused words.
geography: Distinct areas take initial caps: "Black Country," "East Anglia," "Lake District," "Midlands," "Peak District," "West Country"; but areas defined by compass points are lowercase: "the north," "the south-east." Geographical features are generally lowercase, eg "river Thames," "the Wash," "Golden Gate bridge" (but "Mount Everest"). Oceans and seas are uppercase, eg "Atlantic Ocean," "Red Sea." See also "placenames."
ghetto: Plural "ghettoes."
gift: Not a verb.
girl: Female under 18.
girlfriend: No usage note.
girlie, girly: "Girlie" (noun) should not be used; "girly" (adjective, eg "girly clothes"); "girlish behaviour."
glamorous: Not "glamourous."
Glasgow kiss: No usage note.
goalline, goalpost: No usage note.
gobsmacked: Avoid this word.
God: No usage note.
godchild, godfather, godmother, godson, goddaughter: No usage note.
golf: For holes, use numbers: "1st," "2nd," "18th." "Matchplay" is one word, except "World Match Play Championship." "The Open," not "the British Open."
goodness, for goodness sake: No usage note.
goodnight: No usage note.
go-slow: Noun; "go slow" is the verb.
government: Lowercase in all contexts and all countries.
grandad: But "granddaughter."
grand prix: Lowercase: "the British grand prix"; plural "grands prix."
grassroots: No usage note.
Great Britain: England, Wales, and Scotland. To include Northern Ireland, use "UK," not "Britain." The Isle of Man is not part of the UK, but it is part of the British Isles.
great-grandfather, great-great-grandmother: No usage note.
green belt: No usage note.
greenfield site: No usage note.
greenhouse effect: No usage note.
grisly: Means gruesome; "grizzly bear" is spelled differently. See also Commonly confused words.
Gulf war: Of 1991; the Iraq war was a decade later.
Gypsies: Capitalize; recognized as an ethnic group under the Race Relations Act.

H

hajj: No usage note.
half: No hyphen when used adverbially: "you look half dead"; "it was half wine, half water." Hyphen when used adjectivally: "a half-eaten sandwich," "he got it half-price."
half a dozen, half past: No usage note.
halfway, halfwit: No usage note.
Halloween: No usage note.
handicapped: Do not use to refer to people with disabilities or learning difficulties — see "disabled people, disabled persons."
hanging participles: See "dangling participles."
happy-clappy: A derogatory term for evangelical Christians; do not use.
hardline: Adjective; "hardliner" (noun); "take a hard line."
harebrained: Not "hairbrained."
Harrods: No usage note.
hat-trick: No usage note.
HD-DVD: No usage note.
HD-ready: Standard industry term for HDTV-enabled electronics.
headdress: No usage note.
headteacher: One word; not "headmaster," "headmistress."
healthcare: No usage note.
hear, hear: An exclamation of approval; not "here, here."
Heathrow airport: Or simply "Heathrow."
heaven: No usage note.
height: In metres with an imperial conversion, eg "1.7 metres (5ft 7in)."
hell: No usage note.
Her Majesty: The Queen is "HM," never "HRH."
hiccup: Not "hiccough."
hi-fi: No usage note.
high-end: No usage note.
high flyer: No usage note.
highland fling: No usage note.
high street: No usage note.
hijab: A covering for the head and face worn by some Muslim women.
hip-hop: No usage note.
hippy: Plural "hippies."
hi-tech: No usage note.
hoard, horde: "A hoard of treasure"; "a horde (or hordes) of tourists." See also Commonly confused words.
Holocaust: No usage note.
holy grail: No usage note.
Holy Land: No usage note.
homebuyer, homeowner: No usage note.
homeland: But "home town."
homeopathy: No usage note.
homepage: No usage note.
homogeneous, homogenous: "Homogeneous" means uniform, of the same kind; "homogenous" (biology) means having a common descent — the latter is often misused for the former. See also Commonly confused words.
honeybee: No usage note.
Hoover: Trademark; write "vacuum cleaner."
hopefully: Overused; avoid. See also Overused words.
horrendous: Sounds like a combination of "horrific" and "tremendous," but is in fact from the Latin for "fearful"; "horrific" is generally preferable.
hospitals: Capitalize only the place name, eg "Derby district general hospital," "Great Ormond Street children’s hospital," "Royal London hospital"; but "London Clinic."
hotdog: No usage note.
hotspot: No usage note.
houseboat, housebreaker, housebuyer, householder, housekeeper: No usage note.
housewife: Never use.
hovercraft: No usage note.
HTML: A web language.
hummus, humus: "Hummus" you eat; "humus" you put on the garden.
humour, humorist, humorous: No usage note.
hunky dory: No usage note.
hyphens: See Hyphenation. Note also this glossary’s own house convention: prefer one word over a hyphenated pair wherever the compound has become established (eg "handspring," "madhouse," "talkshow" as one word, not hyphenated). Use a hyphen where omitting it would be ambiguous, eg to distinguish "black-cab drivers come under attack" from "black cab-drivers come under attack."

I

icon, iconic: In danger of losing all meaning through overuse. Avoid unless something is genuinely widely regarded as iconic. See also Overused words.
ie: No full points; also "eg," not "e.g." See also [Abbreviations and acronyms].
iMac, iPod: No usage note.
immune to: Not "immune from."
impressionism, impressionist: No usage note.
income tax: No usage note.
independent: No usage note.
in-depth: "In-depth analysis," but "was looked at in depth."
index: Plural "indexes," except in scientific and economic contexts: "indices."
indie: For music, films, and so on; "Indy" is short for a publication named "the Independent."
infer, imply: "To infer" is to deduce something from evidence; "to imply" is to hint at something. See also Commonly confused words.
inflammable: Means the same as "flammable"; the negative is "non-flammable."
infrared: No usage note.
initials: No spaces or points, for businesses or individuals, eg "WH Smith," "PG Wodehouse."
Inland Revenue: No usage note.
inner city: Prefer "city centre."
innuendo, innuendoes: No usage note.
inquiry: Not "enquiry," though "enquire" is fine as a verb.
inshallah: Means "God willing" in Arabic.
install, instalment: No usage note.
instil, instilled, instilling: Followed by "into."
insure: See "ensure, insure, assure."
internet, net, website, web, world wide web: All lowercase.
into: See also "onto."
invalid: Means not valid, or of no worth; do not use to refer to disabled or ill people — see "disabled people, disabled persons."
invariable, invariably: Means unchanging; often wrongly used to mean "hardly ever changing." See also Commonly confused words.
Ireland, Irish Republic: Not "Eire."
Irish Travellers: Capitalize; recognized as a distinct ethnic group under race relations legislation.
ironclad: No usage note.
ironfounder, ironmonger, ironworks: No usage note.
iron curtain: No usage note.
ironically: Avoid when "strangely," "coincidentally," "paradoxically," or "amusingly" is meant. There are times when "ironically" is right, but it is too often misused.
-ise: Not "-ize" at the end of a word, eg "maximise," "synthesise" (exception: "capsize"). This is a British-spelling convention; this standard’s own default is American spelling — see the section introduction.
Islam: The holy book of Islam is the Qur’an, not "Koran."
Islamic festivals: "Ashura" — a day of voluntary fasting for Muslims; Shia Muslims also commemorate the martyrdom of Hussein, a grandson of the prophet, making it a day of mourning for their community. "Eid al-Adha" (Festival of Sacrifice) — celebrates the end of the hajj; "eid" already means "festival," so "Eid festival" is redundant. "Eid al-Fitr" — celebrates the end of Ramadan ("al-fitr" means the breaking of the fast); often called "Eid" in speech, but write the full name, and avoid "Eid al-Fitr festival" for the same reason. "eid mubarak" — not a festival but a greeting ("mubarak" means "may it be blessed"). "Lailat al-Qadr" and "Lailat al-Miraj" — Islamic holy days for study and prayer. "Milad al-Nabi" — celebrates the birth of the prophet; many Muslims disapprove of celebrating it. "Ramadan" — the month of fasting.
Islamist: An advocate or supporter of Islamic fundamentalism.
it is: Truncate to "it’s" where natural, but do not overdo it.
ITV1, ITV2, ITV3, ITV4: No usage note.

J

Jacuzzi: Trademark; call it a "whirlpool bath" or "spa bath" unless it is genuinely a Jacuzzi.
Jeep: Trademark.
jetski: No usage note.
jewellery: No usage note.
job titles: All lowercase: "editor," "governor of the Bank of England," "prime minister."
Joneses: As in "keeping up with the Joneses."
judgment: Not "judgement."
junior: Can be abbreviated to "Jr" but not "Jun" or "Jnr," eg "Sammy Davis Jr."

K

khaki: No usage note.
kick-off: No usage note.
kissogram: No usage note.
Kitemark: Trademark.
kg: For kilograms.
km: For kilometres.
knockout: No usage note.
knots: A measure of nautical miles per hour; do not say "knots per hour."
koala: Not "koala bear."
koi: Not "koi carp."

L

laissez-faire: No usage note.
Lake District, the Lakes: No usage note.
lamppost: No usage note.
Land Registry: The government department that registers title to land in England and Wales.
Land Rover: No usage note.
laptop: Not "notebook" — those are made of paper.
last post: No usage note.
later: Often redundant, since context informs the reader: "the show starts this month," not "the show starts later this month." See also Overused words.
latitude: Written as, eg, "21 deg 14 min S." See also "longitude."
lbw: In cricket.
learned: Not "learnt," except in old-fashioned poetry.
led: The past tense of "lead."
left-click: Of the mouse.
left-hand: No usage note.
leftwing: Adjective; "left wing" (noun).
lepers: Do not use — regarded as inappropriate and stigmatizing; write "people with leprosy."
less, fewer: See "fewer, less."
less developed countries: Use instead of "developing countries" and "third world."
letdown, letup: Nouns; "let down" and "let up" are verbs.
level crossing: No usage note.
liaison: No usage note.
licence, license: "Licence" (noun); "license" (verb).
lifelong: No usage note.
lightbulb: No usage note.
light year: A measure of distance, not time.
Li-Ion: A battery type.
likable: Not "likeable."
like, as if: Never use "like" to mean "as if": "it looks as if he’s finished," not "it looks like he’s finished." See also [Commonly confused words].
like, such as: "Like" excludes; "such as" includes: "cities like Manchester are wonderful" suggests the writer has other cities in mind without naming Manchester as one of the group; "cities such as Manchester" is usually what is meant.
likely: Takes the infinitive ("he is likely to win") or a qualifier ("he will very likely win"), not "he will likely win" — use "he will probably win" for that construction.
liquefy: Not "liquify."
limpid: Means clear or transparent, not limp. See also [Commonly confused words].
linchpin: Not "lynchpin."
lineup, lineout: No usage note.
listed buildings: In England and Wales, "Grade I-listed" buildings (note capital G, roman numeral I) are of exceptional interest; "Grade II*" are particularly important; "Grade II" are of special interest. Scotland and Northern Ireland use "Grade A," "Grade B," "Grade C" instead.
literally: Avoid this word; it’s almost always not needed. See also Overused words.
Lloyds TSB: A bank.
Lloyd’s: Of London; the possessive names are lowercase.
loan, lend: "Loan" (noun); "lend" (verb). See also [Commonly confused words].
loathe: Means detest; not "loath" (reluctant).
lock-in, lockout: Nouns; "lock in," "lock out" are verbs.
logon, login: Nouns; "log on," "log in" are verbs.
London assembly: No usage note.
longitude: Written as, eg, "149 deg 18 min E." See also "latitude."
longtime: Adjective, as in "longtime companion."
long-winded: No usage note.
looking-glass: No usage note.
lottery, national lottery: But "Lotto" and "National Lottery Commission."
lovable: Not "loveable."
lowlife: No usage note.
luvvies: A cliche; do not use.
luxury, luxurious: No usage note.
Lycra: Trademark.
lying in state: No usage note.

M

Mac: Not "Macintosh," unless referring to early Apple computers.
Mac Mini: A brand name for a computer; not "Mac mini."
McDonald’s: No usage note.
magistrates court: No apostrophe.
maharajah: No usage note.
mail order, mailbag, mailvan, mail train: No usage note.
mainmast, mainsail: No usage note.
major: Overused. See also Overused words.
makeover, makeup: No usage note.
mankind: Avoid; use "humankind" or "humanity" — see "disabled people, disabled persons."
manoeuvre, manoeuvring: No usage note.
Marks & Spencer: At first mention, then "M&S."
mass: Lowercase; "mass" is celebrated or said, not "read."
massive: Massively overused; avoid. See also Overused words.
masterful: Means imperious.
masterly: Means skilful. See also Commonly confused words.
matinee: No accent.
matt: "Matt finish."
may, might: "May" implies the possibility remains open: "the tower may have changed the face of architecture forever" (it has been built). "Might" suggests the possibility no longer remains open: "the tower might have changed the face of architecture forever" (if only they had built it). Similarly, "they may have played tennis, or gone boating" suggests uncertainty about what happened; "they might have played tennis if the weather had been dry" means they did not, because it was not dry.
mayor of London: No usage note.
meanwhile: Almost always misused to mean "here’s a slight change of subject."
Meat Loaf: Sings.
meatloaf: Doesn’t sing.
measurements and quantities: Give metric measures, converting to imperial in brackets at first mention only (exceptions: miles and pints). If a rough figure is given in metric, do not convert it to an exact imperial figure, and vice versa — eg if two towns are about 50km apart, convert to "30 miles," not "31.07 miles"; the same applies to rounded currency amounts.
mecca: As in "a mecca for gamblers" — cliche, avoid.
Médecins sans Frontières: An international medical aid charity.
medieval: Not "mediaeval."
meet, met: Not "meet with," "met with someone."
mega: Avoid this word.
megapixel: No usage note.
menswear: No usage note.
metres: See "distances."
metric system: This standard’s own convention is American units by default outside a specifically metric or scientific context — see Numbers, dates, and units; the source convention this entry is adapted from used the metric system throughout, with exceptions for miles and pints, and a bracketed imperial conversion wherever useful.
mexican wave: No usage note.
microphone: Not "mic."
mid: "Mid-90s," "mid-60s." See also "dates."
mid-Atlantic: But "transatlantic."
midday: No usage note.
middle ages: No usage note.
midway: No usage note.
midweek: No usage note.
mileage: No usage note.
millenary, millennium, millennia: No usage note.
million: See "numbers."
mimic, mimicked, mimicking: No usage note.
min: A contraction of "minute"/"minutes," no full point.
mind-set: No usage note.
mineworker: No usage note.
minibus, minicab, miniskirt, minivan: No usage note.
MiniDisc: Trademark.
MiniDV: Trademark.
minuscule: Not "miniscule."
minimum: Plural "minima."
mis-selling: No usage note.
misuse, misused: No usage note.
MLA: A member of the Northern Ireland assembly ("member of the legislative assembly"), eg "Bairbre de Brun MLA."
Moby-Dick: Herman Melville’s novel is, notably, hyphenated.
modelling: No usage note.
modern art: No usage note.
moneys: Not "monies"; "moneyed," not "monied."
more than, over: Generally prefer "more than": "there were more than 20,000 people at the game"; "it will cost more than £100 to get it fixed"; but "she is over 18." "Over" and "under" answer the question "how much?"
morning-after pill: No usage note.
morris dance: No usage note.
Morrisons: No usage note.
mosquito: Plural "mosquitoes."
mother of three: And similar; not "mother-of-three."
motorcar, motorcycle: No usage note.
motorways: Write "M1," not "M1 motorway."
mottoes: No usage note.
mousemat: The thing a computer mouse sits on.
movable: Not "moveable."
MP3: No usage note.
mph: No usage note.
MPs: No usage note.
Mr, Ms, Mrs, Miss: Usually not needed.
MSP: A member of the Scottish parliament, eg "Sir David Steel MSP."
Muhammad: No usage note.
multicultural, multimedia, multimillion: But "multi-ethnic."
multi-function: No usage note.
multi-task, multi-tasking: No usage note.
museums: Capital "M," eg "British Museum," "Natural History Museum," "Victoria and Albert Museum" ("V&A").
music types and terms: "Bebop," "hard bop," "post-bop" (swing and jazz).
Muslim: No usage note.

N

naive, naively, naivety: No accents.
Nasa: No usage note.
nation: Do not use when "country" or "state" is meant; reserve "nation" for people united by language, culture, and history so as to form a distinct group within a larger territory. See also [Commonly confused words].
National Grid: No usage note.
national insurance: No usage note.
national lottery: No usage note.
Native Americans: No usage note.
Nato: No usage note.
naught, nought: "Naught" means nothing; "nought" is the figure 0. See also Commonly confused words.
navy: But "Royal Navy."
Nazi, nazism: No usage note.
nearby: Always one word.
nearsighted, nearsightedness: No usage note.
nerve-racking: No usage note.
Nestlé: No usage note.
never-ending: No usage note.
nevertheless: But "none the less."
new, now: Often redundant. See also Overused words.
New Labour: No usage note.
news agency: No usage note.
newsagent, newsprint, newsreel, newsstand: No usage note.
newspaper titles: Lowercase "the": "the Guardian," "the Sun." Do not write "the [Name] newspaper" for a well-known paper — it’s understood to be one.
New Testament: No usage note.
new year: Lowercase, but "New Year’s Day," "New Year’s Eve."
next of kin: No usage note.
NHS: Or "the health service."
nightcap, nightdress, nightfall, nightgown, nightshade, nightshirt: No usage note.
Nobel prize: "Nobel peace prize," "Nobel prize for literature."
No 1: In the charts, world rankings, and similar.
No 10: Downing Street.
no-brainer: No usage note.
no man’s land: No usage note.
no one: Not "no-one."
nonconformist: No usage note.
none: It is a persistent myth that "none" must take a singular verb; plural is acceptable and often sounds more natural, eg "none of the current squad are good enough."
none the less: But "nevertheless."
nonexistent: No usage note.
north: "North London," "north-east England," "the north-west": all lowercase.
north of the border: No usage note.
notebook, notepaper: But "laptop" for a portable computer.
noticeable: No usage note.
noticeboard: No usage note.
Nottingham Forest, Notts County: No usage note.
Notting Hill carnival: No usage note.
numbers: Spell out one through nine; use integers from 10 to 999,999; thereafter use "1m" or "3.2bn" for sums of money, quantities, or inanimate objects, eg "£10m," "5bn tonnes of coal"; but "million" or "billion" spelled out for people or animals, eg "1 million viewers." No space between the number and the word: "1million," not "1 million." See also Numbers, dates, and units.

O

OAPs, old age pensioners: Do not use; see "pensioners."
obscenities: See "swearwords."
oceans, seas: See "geography."
odds: Long odds (eg "100-1 against") mean something unlikely; shorter odds (eg "10-1") still mean it’s unlikely, but less so; "odds on" (eg "2-1 on") means it is likely — a £2 bet would win only £1 plus the stake.
offhand, off-licence, offside: No usage note.
Oh!: Not "O!"
oil painting: No usage note.
OK: Correct; "okay" is not.
Old Testament: No usage note.
Olympic games: Or just "Olympics."
on board: For a ship or plane, not "aboard."
once-over: No usage note.
one-to-one: No usage note.
ongoing: Prefer "continuous" or "continual."
online: No usage note.
only: Can be ambiguous if not placed next to the word or phrase it modifies: "I have only one ambition" is clearer than "I only have one ambition."
on-screen: No usage note.
on-site: No usage note.
on-the-fly: No usage note.
onto, on to: "He jumped onto the bus"; but "here’s to moving on to different things." "Into" is also one word. See also [Commonly confused words].
Op 58, No 2: A music style reference format.
operating system: On a computer, usually Windows or macOS.
optimise: No usage note.
ordinance: Means a direction or decree.
Ordnance Survey: No usage note.
organisation: No usage note.
Orkney: Not "the Orkney Isles" or "the Orkneys."
outgrow, outgun, outmanoeuvre, outpatient, outsource, outsourcing: No usage note.
outward bound: Avoid this phrase for a generic outdoor course, since it can be mistaken for a reference to a specific outdoor-education organization by that name; use a safer term such as "outdoor adventure" or "adventure training."
overly: Avoid; write "over."
over: See "more than, over."
overpricing: No usage note.
override: No usage note.
overrule: No usage note.
owing to, due to: See "due to, owing to."

P

Pacific Ocean: No usage note.
Palme d’Or: Awarded at the Cannes film festival.
Pandora’s box: No usage note.
panel, panelled, panelling: No usage note.
papier-mache: No usage note.
paralleled: No usage note.
parentheses: See Dashes for this standard’s own preference for the em dash over parenthetical brackets. Square brackets are used within a direct quote only to interpolate essential context the writer of the quote did not supply.
Parkinson’s disease: No usage note.
Parkinson’s law: No usage note.
parliament, parliamentary: No usage note.
Parthenon marbles: No usage note.
party: Lowercase in the name of a political organization, eg "Labour party."
passer-by: Plural "passers-by."
passive voice: See Voice and tense.
password: No usage note.
pasteurise: No usage note.
payback, payday, payout: No usage note.
peacetime: No usage note.
pedaller, peddler, pedlar: "Pedaller" is a cyclist; "peddler" is a drug dealer; "pedlar" is a hawker. See also Commonly confused words.
peer-to-peer: No usage note.
pendant, pendent: "Pendant" (noun); "pendent" (adjective). See also Commonly confused words.
peninsula, peninsular: "Peninsula" (noun); "peninsular" (adjective).
penknife: No usage note.
pensioners: Do not call them "old age pensioners" or "OAPs." Do not use "elderly" for someone under 70.
per: Avoid; prefer plain English: "she earns £30,000 a year" is better than "£30,000 per year." Exception: "miles per hour," abbreviated "mph."
percentages: Write "70%." If the word must be spelled out, write "percent," one word, not "per cent."
percentage rises: A common source of error. An increase from 3% to 5% is a "2 percentage point increase" or a "2-point increase" — it is not a "2% increase," since a 2% increase on 3% would be 3.06%. See also Numbers, dates, and units.
permissible: No usage note.
persons: Prefer "people."
Perspex: Trademark.
phenomenon: Plural "phenomena."
Philips: An electronics company.
Phillips: A screwdriver.
philistine: No usage note.
Phnom Penh: No usage note.
phone: No apostrophe; "telephone" is rarely necessary.
phone numbers: Format as, eg, "01225 585 000" (area code + 6-digit number); "020 8585 0000" (London’s area code is always "020"). Always include the area code. Only include the country code for a number in a different country.
phosphorous, phosphorus: "Phosphorous" (adjective); "phosphorus" (noun).
photocopy: Not "Photostat" or "Xerox" (trademarks).
photo-scanning: No usage note.
Photoshop: No usage note.
piecework: No usage note.
pigeonhole: Verb or noun.
pigsty: Plural "pigsties."
Pilates: Capitalized.
pin, pin number: Not "Pin" or "PIN number."
placename: No usage note.
placenames and venues: A representative list of commonly misspelled or mishandled place names and venues: "Andalucia"; "Asunción" (capital of Paraguay); "Ardoyne" (Belfast), not "the Ardoyne"; "Barons Court"; "Bombay" is now "Mumbai" — write "Mumbai (formerly Bombay)" at first mention, then "Mumbai"; "Burma" is now "Myanmar" — write "Myanmar (previously Burma)" at first mention, then "Burma"; "Burton on Trent"; "Caribbean"; "Coliseum" (London theatre) vs "Colosseum" (Rome); "Derry" or "Co Derry," not "Londonderry"; "Earls Court," no apostrophe; "East Anglia"; "East End," inner east London north of the river; "eastern Europe," "western Europe"; "East Riding of Yorkshire council"; "Eire" should not be used — write "Republic of Ireland" or "Irish Republic"; "the Embankment" (London); "the equator"; "far east," but "Middle East"; "Fife," not "Fyfe"; "the Gambia," not "Gambia"; "the Gulf," not "the Persian" or "Arabian Gulf"; "Haringey" (North London borough); "the Highlands" (Scotland); "Ho Chi Minh City" (formerly Saigon); "Holland" should not stand in for "the Netherlands"; "home counties"; "Ivory Coast," not "the Ivory Coast" or "Côte D’Ivoire"; "King’s Cross"; "King’s Lynn"; "the Lakes," "Lake District"; "House of Lords"; "Lord’s" (cricket ground); "Luxembourg"; "Málaga"; "Mallorca," not "Majorca"; "Marrakech"; "Marseille," not "Marseilles"; "Mecca" (in Saudi Arabia); "Middle East"; "Middlesbrough," not "Middlesborough"; "Midlands" ("east Midlands" but "East Midlands airport," "West Midlands"); "midwest" (US); "the Millennium Dome" at first mention, then "the dome"; "the National Archives"; "the Netherlands," not "Holland," which is only part of the country — the adjective is "Dutch"; "Newcastle-under-Lyme"; "Newcastle upon Tyne"; "New York City," "New York state"; "northern hemisphere"; "north pole"; "Orkney," not "the Orkney Isles" or "the Orkneys"; "Peak District"; "Pearl Harbor" — use American spellings for US place names; "Philippines," inhabited by "Filipinos" (male) and "Filipinas" (female), adjective "Filipino" for both, but "Philippine" for a place ("a Philippine island"); "Potters Bar"; "Regent’s Park"; "Royal Academy of Arts" (then "the Royal Academy"); "Sadler’s Wells"; "St Andrews University," no apostrophe; "Sao Paulo," not "Sao Paolo"; "Savile Row"; "Scandinavia" — Norway, Sweden, Denmark, and Iceland, not Finland; "Shankill Road" (Belfast); "Shetland," or "the Shetland Isles," but never "the Shetlands"; "Shoreham-by-Sea"; "Stansted airport"; "strait of Dover," "strait of Hormuz"; "Tenerife"; "Ukraine," not "the Ukraine"; "University College London," no comma, "UCL" after first mention; "V&A" for "Victoria and Albert Museum"; "west," "western," "the west," "western Europe"; "West Country"; "Westminster Abbey"; "Windermere," not "Lake Windermere"; "Yemen," not "the Yemen"; "Yorkshire" — "North Yorkshire," "South Yorkshire," "West Yorkshire," but "east Yorkshire." See also "geography."
plaster of paris: No usage note.
plateau: Plural "plateaux."
playbill, playgoer, playwright: No usage note.
play-off: No usage note.
plc: Not "PLC."
plug-and-play: No usage note.
plug-in: No usage note.
pocketbook, pocketknife: No usage note.
Pocket PC: A Microsoft product.
poet laureate: No usage note.
point-and-click: No usage note.
pointe: Ballet: "on pointe," not "on point" or "en pointe."
point-to-point: No usage note.
Pokemon: No accents.
Polari: A form of language used mostly by gay men and lesbians, derived in part from slang used by sailors, actors, and prostitutes; treat it as you would other colloquialisms and slang.
pop art: No usage note.
the Pope: But "the pontiff," lowercase.
pop-out: No usage note.
pop-up: No usage note.
Portakabin: Trademark.
Post-It: Trademark.
postcode: No usage note.
postgraduate: No usage note.
postmodern, postmodernist: No usage note.
post-mortem: No usage note.
Post Office: Capitalize when referring to the organization; lowercase "post office" for a generic shop that deals with mail.
postwar: No usage note.
practice, practise: "Practice" (noun); "practise" (verb). See also Commonly confused words.
precis: Singular and plural.
pre-eminent, prefab, prefabricated: No usage note.
premiere: For film; no accent.
Premiership: For English football (the FA Premier League is the governing body, not the competition); in Scotland, "the Premier League."
premises: Of buildings and logic.
preproduction: No usage note.
prepositions: It is a myth, not a grammar rule, that a sentence must not end with a preposition.
pre-Raphaelite: No usage note.
presently: Means "soon," not "at present." See also [Commonly confused words].
president: Lowercase except in a title: "President Bush," but "George Bush, the US president."
the press: Or "the media."
pressurised: Avoid; use "pressured," "put pressure on," or "pressed."
preteen: No hyphen.
preventive: Not "preventative."
prewar: No usage note.
pricey: No usage note.
prima donna: Plural "prima donnas."
principal, principle: "Principal" means first in importance, or the most senior person; "principle" means a standard of conduct. See also Commonly confused words.
prime minister: No usage note.
Prince of Wales: First mention; thereafter "the prince" plus the current name.
printout: No usage note.
Pritt Stik: Trademark.
prizes: Lowercase "p": "Booker prize," "Nobel prize," "Whitbread prize."
probe: A dental implement, not an inquiry or investigation.
prodigal: Means wasteful or extravagant, not "a returned wanderer" — the confusion arises from the biblical parable of the prodigal son. See also Commonly confused words.
profile: A noun, not a verb.
program: For computing; otherwise "programme."
propeller: No usage note.
prophecy, prophesy: "Prophecy" (noun); "prophesy" (verb).
pros and cons: No usage note.
protege: Male and female; no accents.
protest: "Against," "over," or "about."
proviso: Plural "provisos."
Ps and Qs: No usage note.
Puffa: Trademark; say "padded" or "quilted jacket," not "puffa jacket."
pundit: A self-appointed expert.
purchase: As a noun, but use "buy" as a verb.
put, putt: "Put" (athletics); "putt" (golf). See also [Commonly confused words].
pygmy: Plural "pygmies"; lowercase except for members of the Equatorial African ethnic group.
Pyjamas: No usage note.

Q

al-Qaida: No usage note.
Qantas: No usage note.
QC: No usage note.
quarterdeck, quartermaster: No usage note.
the Queen: She is "Her Majesty" or "HM," never "HRH."
Queen’s speech: No usage note.
queueing: Not "queuing."
quicklime, quicksand, quicksilver: No usage note.
quixotic: No usage note.
quizshow: No usage note.
Quorn: Trademark.
quotes: See Quotation marks. Always use "said" rather than alternatives such as "commented" or "explained."
Qur’an: The holy book of Islam, not "Koran."

R

R&B: No usage note.
racecourse, racehorse: No usage note.
racial terminology: Do not use "ethnic" to mean black or Asian people — that is an ethnic minority only in a British context; in a world sense, white people are also an ethnic minority. Avoid "immigrant," which is frequently used incorrectly of people born in Britain and carries negative connotations. Use "black" and "Asian" as adjectives, not nouns: "black people," not "blacks"; "an Asian woman," not "an Asian." Say "African-Caribbean," not "Afro-Caribbean."
rack and ruin: No usage note.
rackets: Not "racquets."
Rada: The Royal Academy of Dramatic Art.
Radio 1, Radio 2, Radio 3, Radio 4, Radio 5 Live: Not "Radio Five Live."
radiographer, radiologist: A radiographer takes X-rays; a radiologist reads them.
radius: Plural "radii."
raft: Something you float on; "a raft of measures" is an overused cliche — avoid. See also Overused words.
railway, railway station: Not the American English "railroad," "train station."
raincoat, rainfall, rainproof: No usage note.
Range Rover: No usage note.
Rangers: Not "Glasgow Rangers."
Ray-Ban: Trademark; "Ray-Bans" is acceptable.
ready-made: No usage note.
real-time: No usage note.
re-, re: Use "re-" (with hyphen) before the vowels "e" or "u" when not pronounced "yu": eg "re-entry," "re-examine," "re-urge." Use "re" (no hyphen) before "a," "i," "o," a "yu"-pronounced "u," or any consonant: eg "rearm," "reassemble," "reiterate," "reorder," "reuse," "rebuild." Exceptions: "re-read"; and cases where confusion with another word would arise: "re-cover" (put a new cover on) vs "recover," "re-form" vs "reform," "re-creation" vs "recreation," "re-sign" vs "resign."
rebrand: No usage note.
recent: Avoid; use the actual date where it’s relevant. See also Overused words.
recognise: No usage note.
recurring: No usage note.
Red Cross: No usage note.
re-establish: No usage note.
Regent’s Park: No usage note.
regime: No usage note.
Region 1: For DVDs; but "region coding."
register office: Not "registry office."
regrettable: No usage note.
removable: No usage note.
reopen: No usage note.
replaceable: No usage note.
repellant, repellent: "Repellant" (noun); "repellent" (adjective).
repertoire: An individual’s range of skills or roles.
repertory: A selection of works a theatre or dance company might perform. See also Commonly confused words.
reported speech: When a past-tense comment is reported, use the past perfect: "'I saw him at the game'" becomes "she said she had seen him at the game," not "she said she saw him at the game."
respondent: No usage note.
restaurateur: Not "restauranteur."
reuse: No usage note.
the Rev: At first mention, thereafter use the courtesy title: eg "the Rev Joan Smith," subsequently "Ms Smith." Never "Reverend Smith," "the Reverend Smith," or "Rev Smith."
rickety: No usage note.
ricochet, ricocheted, ricocheting: No usage note.
riffle, rifle: "Riffle" is to flick through a book, newspaper, or magazine; "rifle" is to search or ransack, eg "rifle goods from a shop." See also Commonly confused words.
right-click: No usage note.
right-hand: No usage note.
rivers: See "geography."
riveted, riveting: No usage note.
roadside: No usage note.
rock’n’roll: One word.
Rollerblade: Trademark; say "inline skates" or "rollerskates."
rollercoaster: No usage note.
roll out, roll-out: "Roll out" (verb); "roll-out" (noun).
Rolls-Royce: No usage note.
roughshod: No usage note.
routeing, routing: "Routeing" buses through a city centre, after "routing" the protesters.
the Rovers Return: From Coronation Street; no apostrophe.
Royal Air Force: Or "RAF."
Royal Ballet: No usage note.
royal family: No usage note.
Royal Mail: No usage note.
Royal Opera, Royal Opera House: No usage note.
royal parks: No usage note.
RSPB, RSPCA: No usage note.
rugby league, rugby union: No usage note.
Rule, Britannia!: No usage note.
russian roulette: No usage note.

S

Saatchi: No usage note.
Safeway: Now "Morrisons."
Sainsbury’s: For the stores; the company’s name is "J Sainsbury plc."
Saints: In running text, spell in full: "Saint John," "Saint Paul." For town and church names, abbreviate: "St" (no point), eg "St Mirren," "St Stephen’s church."
St John Ambulance: Not "St John’s," and no need for "Brigade."
saleable: No usage note.
Salvation Army: Never "the Sally Army."
scalable: Not "scaleable."
schoolboy, schoolgirl, schoolchildren, schoolroom: No usage note.
schoolteacher: No usage note.
schools: Lowercase the type of school after a proper name, eg "Alfred Salter primary school."
school years: "Year 2," "year 10," "key stage 1."
science fiction: Not "sci-fi."
ScotchTape: Trademark; say "sticky tape."
scotch whisky, scotch mist: No usage note.
Scotland Office: Not "Scottish Office."
Scottish executive: No usage note.
Scottish parliament: Members are "MSPs."
scottish terrier: No usage note.
scouse, scouser: Avoid.
screamers: See Exclamation and question marks.
screen edge: No usage note.
screen-grab, screen-grabber: No usage note.
screensaver: No usage note.
screenshot: No usage note.
seas, oceans: See "geography."
seacoast, seaplane, seaport, seashore, seaside: No usage note.
seaweed: No usage note.
sea change, sea level, sea serpent, sea sickness: No usage note.
seal pups: No usage note.
seasons: "Spring," "summer," "autumn," "winter" — all lowercase.
second hand, second-hand: "Second hand" of a clock; "second-hand" for previously owned.
self-control, self-defence, self-esteem, self-respect: No usage note.
Sellotape: Trademark; say "sticky tape."
senior: Abbreviate to "Sr," not "Sen" or "Snr," eg "George Bush Sr."
September 11: "9/11" is acceptable. Dates are usually written "11 September," but this specific date is conventionally written the American way, "September 11."
the services: Or "the armed forces."
setback: No usage note.
set-up, set up: "Set-up" (adjective and noun); "set up" (verb). Never "setup."
shakeout, shakeup: No usage note.
Shakespearean: No usage note.
shareholder: No usage note.
sheepdog: No usage note.
sheikh: No usage note.
ships: Not feminine — "it ran aground," not "she ran aground."
shipbuilding, shipbuilder, shipmate, shipowner, shipyard: No usage note.
shoo-in: Not "shoe-in."
shoot-'em-up: No usage note.
shopkeeper: No usage note.
shortcut: No usage note.
shortlist: No usage note.
Siamese twins: Do not use; see "conjoined twins."
side-effects: No usage note.
sidestreet: No usage note.
silicon, silicone: "Silicon" is for computer chips; "silicone" is for breast implants. See also Commonly confused words.
Singin' in the Rain: No usage note.
singular or plural: A common mistake is to refer to a company or a local government agency in the plural: "Virgin Mobile have sponsored." A single company is singular: "Virgin Mobile has sponsored." Sports teams take plural verbs: "Wednesday were relegated again"; but in a business context a sports club is singular like any other company, eg "Leeds United posted a financial loss." See also Collective nouns.
Sinn Féin: No usage note.
sizeable: No usage note.
ski, skis, skier, skied, skiing: No usage note.
slidable: Not "slideable."
smallholding: No usage note.
Smartphone: No usage note.
Smithsonian Institution: Not "Institute."
snowplough: No usage note.
socialism, socialist: No usage note.
sod’s law: No usage note.
Solar System: No usage note.
Sotheby’s: No usage note.
soundbite: No usage note.
soundcard: A computer component.
south: "South London," "south-west England," "the south-east": all lowercase.
South Bank: No usage note.
southern hemisphere: No usage note.
south pole: No usage note.
spaghetti western: No usage note.
span of years: See "dates."
spastic: Do not use.
the Speaker: For the House of Commons; but "deputy speaker" (of whom there are several).
special: Usually redundant. See also Overused words.
specification: Not "spec."
spelled, spelt: Either works; prefer "spelt."
spicy: Not "spicey."
Spider-Man: No usage note.
split infinitives: It is acceptable to sensibly split an infinitive, and stubbornly avoiding it can sound awkward or introduce ambiguity: "the workers are declared strongly to favour a strike" leaves it unclear whether the declaration or the favouring is strong.
spoiled, spoilt: "She spoiled her son"; "he was a spoilt brat."
spokesman, spokeswoman: Prefer "spokesperson."
spoonful: Plural "spoonfuls."
springboard: No usage note.
standalone: No usage note.
stand-by, stand by: "Stand-by" (adjective); "stand by" (verb).
start-up: No usage note.
state of the union address: US usage.
stationary, stationery: "Stationary" means not moving; "stationery" means writing materials. See also Commonly confused words.
steadfast: No usage note.
steamboat, steamship, steam engine, steamhammer: No usage note.
step change: "Change" is usually adequate on its own.
stepfather, stepmother: No usage note.
sterling: The pound.
sticky-back plastic: No usage note.
stiletto: Plural "stilettos."
still life: Plural "still lifes."
stilton: No usage note.
stock market, stock exchange: No usage note.
stopgap: No usage note.
straightforward: No usage note.
streetwise: No usage note.
strippergram: No usage note.
stumbling block: No usage note.
subcommittee, subcontinent, subeditor, sublet: No usage note.
sublieutenant, submenu, subplot, subsection: No usage note.
sublicense: No usage note.
submarines: Are boats, not ships.
suchlike: No usage note.
sudoku: No usage note.
summer: No usage note.
supermodel: Overused; "model" is usually sufficient.
supersede: No usage note.
sure-fire: No usage note.
Sure Start: No usage note.
surge: Prefer "rise" or "increase" where that is the meaning.
surrealism, surrealist: No usage note.
swap: Not "swop."
swearwords: Do not use.
swingeing: No usage note.
synthesis, synthesise, synthesiser: No usage note.

T

tableau: Plural "tableaux."
takeoff: Noun; "take off" is the verb.
takeover: No usage note.
talkshow: No usage note.
talk to: Not "talk with."
tam o’shanter: A woollen cap.
Tannoy: Trademark.
taoiseach: The Irish prime minister.
targeted, targeting: No usage note.
tariff: No usage note.
tarot cards: No usage note.
taskforce: No usage note.
taskmaster: No usage note.
Tate: A group of British art galleries: "Tate Britain" (Millbank, London, British art from the 16th century), "Tate Modern" (Southwark), "Tate Liverpool," "Tate St Ives."
teacup, teapot, teaspoon, teabag: No usage note.
team-mate: No usage note.
teams: See "singular or plural."
teargas: No usage note.
Teasmade: Trademark; say "teamaker."
Teesside: No usage note.
teetotaller: No usage note.
Teflon: Trademark; say "non-stick pan."
telephone numbers: See "phone numbers."
Teletubbies: No usage note.
temazepam: No usage note.
temperatures: Where both scales are given for a general audience, format as "23C (73F)," "-3C (27F)," with no degree symbol. Avoid "centigrade" in favour of "celsius," to avoid any confusion with the historical meaning of "centigrade" as the 100th part of a grade.
Ten Commandments: No usage note.
tendinitis: Not "tendonitis."
tenses: See Voice and tense.
terrace houses: Not "terraced."
Terrence Higgins Trust: No usage note.
Tesco: Not "Tesco’s."
Test: In cricket: "the third Test."
textbook: No usage note.
textbox: No usage note.
that: Do not omit "that" where the sentence grammatically requires it, but do not automatically insert it after "said" either. See also "that or which."
that, which: See <<"That" and "which">>.
the: Lowercase for newspapers ("the Guardian"), magazines ("the New Statesman"), pubs, rock bands ("the Beatles"), and sports grounds ("the Oval"). Uppercase for books ("The Lord of the Rings"), films ("The Matrix"), poems ("The Waste Land"), television shows ("The West Wing"), and some place names ("The Hague").
theatregoer: No usage note.
theirs: Never an apostrophe.
Thermos: Trademark; say "vacuum flask."
there is: Truncate to "there’s" where natural.
thinktank: No usage note.
third party: Not hyphenated.
Third Reich: No usage note.
third way: No usage note.
third world: Do not use; prefer "less developed countries."
this, that: "This" looks forward; "that" looks back.
thoroughbred, thoroughgoing: No usage note.
threefold, threescore: No usage note.
thumbs up: No usage note.
thunderstorm: No usage note.
time-out, time out: "Time-out" (noun); "time out" (verb). "Time Out" is a magazine and a trademark.
tidewater: No usage note.
times: This standard’s own convention is 24-hour format — see Numbers, dates, and units — which differs from a house style using "1am," "6.30pm" for a general audience; the source convention this entry is adapted from used the 12-hour form throughout, without the 24-hour clock.
time-saver: No usage note.
time zone: No usage note.
tinfoil: No usage note.
titbit: Not "tidbit" (US spelling).
titles: "AM" (assembly member): a member of the Welsh assembly, eg "Rhodri Morgan AM."
T-junction: No usage note.
tomato: Plural "tomatoes."
tonne: Not "ton."
towards: Not "toward."
top hat: No usage note.
top 10, top 40: And similar.
tortuous, torturous: "Tortuous" describes a road that winds or twists; "torturous" describes an experience involving pain or suffering. See also Commonly confused words.
Tory party: Prefer "Conservative party."
totalled: No usage note.
touchdown: No usage note.
town councillor, town hall: No usage note.
trade union, trade unionist: No usage note.
tragic: Use with care; avoid cliches such as "tragic accident."
transatlantic: No usage note.
Transport for London: No usage note.
Trans-Siberian railway: No usage note.
Traveller, Travellers: Uppercase when referring to a group such as Irish Travellers, recognized as a distinct ethnic group under race relations legislation.
trip-hop: No usage note.
tropic of cancer, tropic of capricorn: No usage note.
the Troubles: Refers to the conflict in Northern Ireland.
try to: Never "try and."
tsar: Not "czar."
T-shirt: No usage note.
the tube: Lowercase ("London Underground" is the name of the company); individual lines are named thus: "Jubilee line," "Northern line."
turnover: Noun; "turn over" is the verb.
21st century: No usage note.
twofold: No usage note.
tying: No usage note.

U

UK: No usage note.
UN: No need to spell out "United Nations."
unbiased: No usage note.
unchristian: No usage note.
uncooperative: No usage note.
under way: No usage note.
underage: No usage note.
underestimate, understate: No usage note.
underground: See "the tube."
uninterested: Means not taking an interest; not a synonym for "disinterested." See "disinterested" and Commonly confused words.
union flag: Not "union jack."
United Kingdom: England, Wales, Scotland, and Northern Ireland; no need to write in full — say "Britain" or "the UK."
universities: Capitalize, eg "Sheffield University," "Johns Hopkins University." "University College London," no comma, "UCL" after first mention.
Unknown Soldier: "The tomb of the Unknown Soldier."
unmistakable: No usage note.
upgradable: No usage note.
upmarket: No usage note.
upon: Prefer "on."
up to date, up-to-date: "Up to date" on its own, but "in an up-to-date fashion" as a modifier.
US: For "United States," not "USA"; no need to spell out. "America" is also acceptable.
usable: Not "useable."
Usenet: No usage note.
username: No usage note.
utopian: No usage note.
u-turn: No usage note.

V

versus: Not "vs" or "v."
VAT: No usage note.
VE Day: 8 May 1945; "VJ Day" is 15 August 1945.
venetian blind: No usage note.
veranda: Not "verandah."
very: Usually redundant. Avoid using this word. See also [Overused words].
veto, vetoes, vetoed, vetoing: No usage note.
vicar: A cleric of the Anglican church, not of any other denomination.
vice-chairman, vice-president: No usage note.
vie, vying: No usage note.
vis-a-vis: No accent.
vocal cords: Not "chords."
voiceover: No usage note.
Voice over IP: "VoIP" after first instance; "broadband phone" is also acceptable.
volcano: Plural "volcanos."

W

Wales Office: Not "Welsh Office."
walking stick: No usage note.
Wall’s: A brand of ice cream and sausages.
wall-to-wall: No usage note.
Wap: Wireless application protocol, as in "Wap phone."
wars: "First world war," "second world war," "Gulf war" (1991), "Iraq war" (2003), "Crimean war," "Boer war," "Korean war," "Vietnam war," "the hundred years war."
watercolour, watercourse, watermark, waterproof: No usage note.
waterworks: No usage note.
web, website: No usage note.
web browser: Avoid using "explorer" or naming a specific browser generically.
webcam: No usage note.
webcast: No usage note.
web link: No usage note.
webpage: No usage note.
webserver: No usage note.
Weight Watchers: Trademark.
wellbeing: No usage note.
Welsh assembly: Members are "AMs."
western: A cowboy film.
west coast mainline: No usage note.
whence: Means "where from," so "from whence" is redundant.
whereabouts: Singular: "her whereabouts is not known."
while: Not "whilst."
whisky: Plural "whiskies"; but Irish and US "whiskey."
whistleblower: No usage note.
Whitsuntide: Not "Whitsun."
who, whom: Usually "who."
wicketkeeper: No usage note.
wide awake: No usage note.
Wi-Fi: Trademark; the generic term is "wireless computer network."
Wimpey: Houses (a housebuilder).
Wimpy: Burgers (a restaurant chain).
Windermere: Not "Lake Windermere"; also the name of the town.
Windows: Made by Microsoft.
wines: Lowercase, whether named for a region (eg "beaujolais," "bordeaux," "champagne") or a grape variety (eg "cabernet sauvignon," "chardonnay," "merlot"). The region itself, capitalized, may still appear: "a burgundy from Burgundy."
winter: No usage note.
wintry: No usage note.
wipeout, wipe out: "Wipeout" (noun); "wipe out" (verb).
withhold: No usage note.
wits' end: No usage note.
wiz: As in "a wiz at maths."
WMV HD: A high-definition video format from Microsoft.
woeful: No usage note.
womenswear: No usage note.
Woolworths: No usage note.
Microsoft Word: No usage note.
word processor: No usage note.
world championship: No usage note.
World Cup: Football, cricket, rugby.
world heritage site: No usage note.
World Trade Centre: But "twin towers."
worldwide: No usage note.
WWF: At first mention, "WWF (formerly the World Wide Fund for Nature)."

X

Xbox, Xbox 360: No usage note.
Xerox: Trademark; say "photocopy."
Xmas: Avoid; use "Christmas."
x-ray: No usage note.

Y

Yahoo: The company’s own styling adds an exclamation mark ("Yahoo!"), but write "Yahoo" in running prose.
years: See "dates."
Yellow Pages: Trademark.
yo-yo: No usage note.
yorkshire terrier: No usage note.
Yorkshire Ripper: No usage note.

Z

zero: No usage note.
zhoosh: An example of Polari (see "Polari"); has various shades of meaning as noun, verb, and adjective ("zhooshy").
zigzag: No usage note.

Countries and nationalities

Favour simplicity over precision in most contexts: "Britain" rather than "Great Britain" or "the United Kingdom," "America" rather than "the United States." Where precision matters: "Great Britain" is England, Scotland, and Wales; together with Northern Ireland these make up "the United Kingdom." "The Netherlands," not "Holland" — Holland is only two of the country’s provinces. "Ireland" on its own — it is a republic, but not "the Republic of Ireland," and not, in English, "Eire." "The United States" and "United States citizens" is sometimes needed for precision, since "Americans" also covers everyone from Canada to Cape Horn colloquially, if imprecisely. "EU" is fine after a first mention of "the European Union." "Scandinavia" primarily means Norway and Sweden, often extended to include Denmark and Iceland; with Finland, these make up "the Nordic countries." Respect a country’s stated preference for its own name: "Côte d’Ivoire," "Myanmar," "Burkina Faso." Former Soviet republics: "Belarus" (not "Belorussia"), "Kazakhstan," "Kyrgyzstan" (not "Kirgizia"), "Moldova" (not "Moldavia"), "Tajikistan," "Turkmenistan," "Uzbekistan."

Transliteration of foreign names

Arabic: Omit "al-" from a name where it reads naturally without it; include it (lowercase, followed by a hyphen) where the name looks odd without it. "Osama bin Laden" becomes "Mr bin Laden" on second mention.
Bangladeshi: Where a name includes the Islamic definite article, write it lowercase and without hyphens: "Mujib ur Rahman."
Chinese: Follow Pinyin spelling, which has replaced the older Wade-Giles system, except for historical figures and people or places outside mainland China: "Beijing," not "Peking"; "Mao Zedong," not "Mao Tse-tung." Pinyin spelling has no hyphens: "Deng Xiaoping," "Guangzhou." Exceptions that keep a hyphen: "Chiang Kai-shek," "Hong Kong," "Li Ka-shing." The family name comes first in Chinese, Singaporean, and Vietnamese names, so "Deng Xiaoping" becomes "Mr Deng" on a later mention.
Dutch: With a first name and surname together, "van" and "den" are lowercase: "Dries van Agt." Without the first name: "Mr Van Agt." These rules do not always apply to Dutch names in Belgium and South Africa.
French: A "de" is usually lowercase unless it starts a sentence: "Charles de Gaulle," but "De Gaulle" to open a sentence.
German: A "von" is uppercase only at the start of a sentence.
Japanese: The Japanese language puts the family name first (Koizumi Junichiro), but this is generally reversed in English-language contexts: "Junichiro Koizumi."
Korean: The family name comes first: "Kim" in "Kim Dae-jung."
Pakistani: Where a name includes the Islamic definite article "ul," write it lowercase and without hyphens: "Zia ul Haq."
Russian: Transliteration is inherently imprecise; a few rules of thumb favour simplicity over phonetic accuracy: no "y" before "e" except at the start of a word ("Belarus," "perestroika," but "Yeltsin"); words ending "-ski," "-skii," or "-sky" become "-sky"; a sound pronounced "yo" is usually spelled "e" ("Fedorov," "Gorbachev," not "Fyodorov").
Ukrainian: Ukrainian has no "g," so "Yevhen" (not "Yevgeny"), "Ihor" (not "Igor"), "Luhansk" (not "Lugansk"). The currency is the "hryvnia."

Honorifics and personal titles

The overriding principle is to treat people with respect — usually meaning the title they themselves use. Do not use "Mr," "Mrs," "Miss," "Ms," or "Dr" on first mention; a plain first-name-and-surname combination is enough. On later mentions, precede the name with the appropriate title. Knights, dames, princes, and other titled figures are given their title on first and subsequent mentions. Someone better known by an informal or familiar name may be introduced that way, then referred to by title thereafter.

A title is not necessary in a heading or caption (the surname is). No titles for the dead, except where the death itself is the subject being written about.

"Ms" is acceptable, though some style guides consider it stylistically awkward; use "Miss" or "Mrs" only where the person’s own preference is known, since "Miss" does not itself imply marital status.

Take care with foreign titles — some, such as certain Malaysian honorifics, are complex enough that omitting the title and using the name alone, consistently, is the more reliable choice.

Use "Dr" only for qualified medical people, unless no better alternative is known. Reserve "Professor" for someone who holds an academic chair, not just any university post.

Get a title right if used at all: a specific military rank such as "Rear-Admiral" should not be shortened to a more general one like "Admiral" on first mention.

A title tied to an office ("Governor," "President," "the Rev") reverts to "Mr," "Mrs," or the person’s own preferred title on second mention, rather than repeating the office title throughout.

Avoid joining an office and a name into one construction: "Prime Minister Smith" reads as a single compound noun rather than a title followed by a name; "the prime minister, Smith," or simply "Smith" after first mention, reads more naturally.

Omit middle initials unless needed to distinguish between two people who share a name, eg a parent and child with the same name ("Smith Jr").

Some titles function as names and take initial capitals even though they also describe an office — "the Archbishop of Canterbury." To describe the office rather than the specific individual, use lowercase: "the next archbishop of Canterbury will be a woman."

Grammar

The presentational and word-choice conventions elsewhere in this standard assume grammatically correct prose. This section states the specific rules most often gotten wrong in technical writing.

Split infinitives are permitted where the alternative is awkward. "To boldly go" is grammatically fine; do not contort a sentence to avoid placing an adverb between "to" and the verb it modifies. Prefer the unsplit form only where it reads at least as naturally.
Avoid a dangling participle — an introductory participial phrase whose implied subject does not match the sentence’s actual subject. "Having configured the server, the request succeeded" wrongly implies the request did the configuring; write "Having configured the server, we sent the request" or "After the server was configured, the request succeeded."
Use the subjunctive mood for a hypothetical, contrary-to-fact, or wished- for condition: "If the build were reproducible" (not "was"), "I wish the test suite were faster." The subjunctive uses "were" for all persons in this construction, not just plural ones.
A gerund takes a possessive adjective when it is the true subject of the clause: "We appreciated Priya’s explaining the tradeoffs" (the explaining is the point, not Priya), not "We appreciated Priya explaining the tradeoffs."
Use "an" before a vowel sound, not before a written vowel — "an SQL query" (pronounced "ess-cue-el"), "a Unix system" (pronounced "you-nix"), "an hour," "a European." The rule tracks pronunciation, not spelling.

References

A List Apart / Aimee Gonzalez-Santos (2018). Standards for Writing Accessibly. — The source for the chronological-sequencing and device-agnostic action-verb conventions in Instructional steps.
Google (n.d.). Google Developer Documentation Style Guide: In-page style guide. — The source for the product/tool/binary-name capitalization guidance in Terminology.
OLD-NOTES.md, OLD-NOTES-2.md (internal reference documents). — The source for Grammar and the Latin binomial, classical-music, and biblical citation conventions in Specialized referencing conventions.
Associated Press. The Associated Press Stylebook. — The reference work for American news style.
O’Reilly Media. O’Reilly Style Guide and Word List. — The source for the comma, quotation-mark, apostrophe, dash, hyphenation, and exclamation/question-mark conventions in Commas, Quotation marks, Apostrophes, Dashes, Hyphenation, and Exclamation and question marks, and for the heading-formatting and nested-list/variable-list conventions in Headings and Lists.
PayPal API Standards (community fork). API Style Guide: Document Semantics, Formatting, and Naming. — The source for the RFC 2119 keyword-declaration convention in Normative language, and for the URI Template placeholder syntax in Placeholders.
The Economist. Writing with Style. — The Economist’s style guide.
Wikipedia. Signs of AI writing. — Also various "humanizer" skills that are based on this guide, such as Zed’s.

A more extensive list of style guides is maintained on Wikipedia.