7 Uses, 1 Misuse
The colon (:) most commonly either marks an introduction or enumeration or signals apposition or equality to connect one clause with another one that explains the first. It is also used sometimes as the equivalent of an em-dash, and it has some specialized uses as a notation after a formal salutation and in certain types of citations.
480 Use a colon to link two separate clauses or phrases when you need to indicate a step forward from the first to the second—as when the second part explains the first part or provides an example.
• It was nothing, he said: only a little accident. (James Joyce)
• Whichever way she turned, an ironical implication confronted her: she had the exasperated sense of having walked into the trap of some stupid practical joke. (Edith Wharton)
• Einstein was utterly reticent about his personal life: a “puritanical reserve” was necessary, he said, to a scientist seeking truth. (C. P. Snow)
• Once you admit that you can change the object of a strongly felt affection, you undermine the whole structure of love and marriage, the whole philosophy of Shakespeare’s sonnet: this had been the approved, though unspoken, opinion of the rectory and its mental acres of upper air. (Muriel Spark)
• Every generation takes it for granted that development will continue in a straight line: the stupider the human being, the more does he take it for granted. (Hilaire Belloc)
481 Use a colon to introduce a list—especially one that is enumerated or broken down into subparagraphs. [The fourth bulleted item exemplifies legal style only.]
• The passage holds two of her stately passions: a sympathy for animals and a pleasure in history’s glacial movement, with its cumulative shifts of sensibility. (John Updike)
• It is all there: the pity, the pride, the just contempt, the righteous but controlled anger, the infinite compassion. (John Simon)
• Inevitably, liberalism tries to meet the challenge of communism by means of the approved procedures that follow from liberal principles: plenty of talk and free speech—negotiations, as talk between nations is called; the appeal to man’s better side, his rationality and supposed common interests in peace, disarmament, and a lift in the general standard of living; reduction of tensions; avoidance of risky confrontations; exchange and Truth programs to prove to the communists the goodness of our intentions; reform and economic improvement for everybody in the world; in short, peaceful coexistence phasing into appeasement and collaboration. (James Burnham)
• 4.1 Preparation for implementation of plain-writing requirements.
(A) In general. No later than 9 months after the date of enactment of this Act, the head of each agency must:
(1) designate one or more senior officials within the agency to oversee the agency implementation of this Act;
(2) communicate the requirements of this Act to the employees of the agency;
(3) train employees of the agency in plain writing;
(4) establish a process for overseeing the ongoing compliance of the agency with the requirements of this Act;
(5) create and maintain a plain-writing section of the agency’s website as required under § 4.1(B) that is accessible from the homepage of the agency’s website; and
(6) designate one or more agency points-of-contact to receive and respond to public input on:
(a) agency implementation of this Act; and
(b) the agency reports required under § 5.
(Plain Writing Act of 2010 [as presented in Garner, The Redbook: A Manual on Legal Style, 3rd ed. (St. Paul: West, 2013), 548, 549])
482 Use a colon to introduce a wholly self-contained quotation, especially a long one. (A comma is often proper as well in this context. [See § 457.])
• His wife said: “If the rumors I hear are true, enough Tlingits have filtered in to wipe us out.” (James Michener)
• An aged Halberdier, much decorated for long years of good conduct, said: “I’ll get Captain McKinney.” (Evelyn Waugh)
• At her own death, when the locked box she always kept on her bedside table was finally opened, all it contained was a letter from Rob with the notation in Elizabeth’s hand: “The last letter he ever wrote.” (Helene Hanff)
• Dr. Armstrong said warmly: “This speeding’s all wrong—all wrong! Young men like you are a danger to the community.” (Agatha Christie)
483 Use a colon to introduce a question. (Capitalization is optional after this colon.)
• That is quite true, and out of it arises another question: may the writer take the reader into his confidence about his characters? (E. M. Forster)
• The matter at issue is: What kind of people like Jane Austen? (Lionel Trilling) (A comma would be proper here as well. [See § 461.])
• Well, then let me ask you short and sweet: is Mrs. Linde getting a job in the bank? (Henrik Ibsen)
484 Use a colon after the salutation in formal correspondence. (A comma is acceptable in informal letters.)
• Dear Sir:. . . . (Samuel Johnson to James Boswell)
• Dear Mrs. Meloney:. . . . (Theodore Roosevelt to Mrs. William Brown Meloney)
• Dear Dr. Canby:. . . . (E. B. White to Henry Seidel Canby)
485 Use a colon to separate hours from minutes and certain parts of citations in which its use is traditional.
• At 5:10 a.m., the el train from the Morse stop in Chicago to the Davis stop in Evanston is surprisingly safe for young white women. (Tina Fey)
• The torments of hell are expressed sometimes by weeping and gnashing of teeth (as Matt. 8:12), sometimes by the worm of conscience (as Isa. 66:24, and Mark 9:44, 46, 48). (Thomas Hobbes)
• Century Magazine 32 (1886): 934. (James I. Robertson Jr.)
486 Use a lowercase letter after a colon (unless the first word is a proper noun) when the colon is used within a sentence, even if it introduces your own independent clause. Capitalize the first word after a colon when the colon introduces more than one sentence, a direct question, or speech in dialogue.
• My next thought concerned the choice of an impression, or effect, to be conveyed: and here I may as well observe that, throughout the construction, I kept steadily in view the design of rendering the work universally appreciable. (Edgar Allan Poe)
• Justice Brennan added a further element to the test he laid down in the Roth case: that, to be bannable, material must be “utterly without redeeming social value.” (Anthony Lewis)
• This at least I know to be a mistake: an instance of the pathetic fallacy (angry cloud, proud mountain, presumptuous little Beaujolais) by which we ascribe animate qualities to inanimate phenomena. (Christopher Hitchens)
• The “nationalization of slavery” rested on an assumption shared with the abolitionists: the survival of the South’s slave-labor system required the active collaboration of the federal government. (Bruce Levine)
487 Don’t use a colon to introduce a quotation or list that blends into the syntax of your sentence.
Not this: I recall quite clearly—she told him to: “bring the child straight home.”
But this: I recall quite clearly—she told him to “bring the child straight home.”
Not this: These boys possess what Jane calls: “a one-track mind.”
But this: These boys possess what Jane calls “a one-track mind.”
Not this: Overwhelmed and unprepared, local officials asked the federal government for: “all the help they could get.”
But this: Overwhelmed and unprepared, local officials asked the federal government for “all the help they could get.”