dashes see punctuation.
data It cannot be emphasised enough that this is a plural (singular, datum), despite its almost universal use as a singular noun. Do not be cowed by the majority.
dates month, day, year, in that order, with no commas:
| July 5th | 1996–99 |
| Monday July 5th | 2005–10 |
| July 5th 2009 | 1998–2009 |
| July 27th–August 3rd 2010 1990s | |
| July 2002 |
Do not write on June 10th–14th; prefer between June 10th and 14th. If, say, ministers are to meet over two days, write on December 14th and 15th.
Do not burden the reader with dates of no significance, but give a date rather than just last week, this week or next week (or, indeed, last month or next month), which can cause confusion.
Dates are often crucial to an account of events, but sentences (and, even more, articles) that begin with a date can be clumsy and off-putting. This week Congress is due to consider the matter is often better put as Congress is due to consider the matter this week. The effect is even more numbing if a comma is inserted: This week, Congress is due to consider the matter, though this construction is sometimes merited when emphasis is needed on the date.
Dates that require AD or BC should be set as one unhyphenated word (76AD, 55BC). The same applies to CE (common era) and BCE (before common era), though neither is used in The Economist.
deal (verb) Transitively, deal means distribute: “He was dealt two aces, two kings and a six.” Intransitively, deal means engage in business. Do not deal drugs, horses, weapons, etc; deal in them.
decimate means to destroy a proportion (originally a tenth) of a group of people or things, not to destroy them all or nearly all.
demographics used not to be a word at all, but has become a useful term for facts about births and deaths, and the size and distribution of population, and it would be foolish to ban it.
deprecate, depreciate To deprecate is to argue or plead against (by prayer or otherwise). To depreciate is to lower in value.
different from not to or than.
dilemma Not just any old awkwardness but one with horns, being, properly, a form of argument (the horned syllogism) in which you find yourself committed to accept one of two propositions each of which contradicts your original contention. Thus a dilemma offers the choice between two alternatives, each with equally nasty consequences.
discreet, discrete Discreet means circumspect or prudent. Discrete means separate or distinct. Remember that “Questions are never indiscreet. Answers sometimes are.” (Oscar Wilde)
disinterested means impartial; uninterested means indifferent. “Disinterested curiosity is the lifeblood of civilisation.” (G.M. Trevelyan)
douse, dowse Douse means to throw water over something or extinguish a light or a fire. Dowse means to search for underground water with a divining rod.
down to down to earth yes, but “Occasional court victories are not down to human rights.” (The Economist) No: down to does not mean attributable to, the responsibility of or even up to (It’s up to you). Use caused by or the result of.
due process is a technical term, or piece of jargon, which was first used in England in 1355. It comes in two forms, substantive due process, which relates to the duties of governments to act rationally and proportionally when doing anything that affects citizens’ rights, and procedural due process, which relates to the need for fair procedures. If you use the expression, make sure it is clear what you mean by it.
due to when used to mean caused by must follow a noun, as in The cancellation, due to rain, of … Do not write It was cancelled due to rain. If you mean because of and for some reason are reluctant to say it, you probably want owing to. It was cancelled owing to rain is all right.
Dutch names see names.