Q. Both CMOS 10.27 and Merriam-Webster style “post-traumatic stress disorder” that way, with a hyphen, but it occurs to me that since PTSD takes hold in the wake of traumatic stress, the prefix post- applies to “traumatic stress.” So shouldn’t the spelled-out term be styled “post–traumatic stress disorder,” with an en dash?
A. You’re right: It would make sense to spell post-traumatic stress disorder with an en dash. In fact, we could have used your editorial wisdom back in 2003, when we added posttraumatic to the fifteenth edition of CMOS to show that the prefix post- forms one-word compounds even if the result is two consecutive t’s.
That decision would have reflected the spelling posttraumatic in a list of 125 compounds formed with post- under the entry for that prefix in the then-current tenth edition of Merriam-Webster’s Collegiate Dictionary.
Still, we must have failed to register the hyphen in Merriam-Webster’s separate entry for post-traumatic stress disorder, which followed entries for posttranscriptional, posttransfusion, and posttranslational—all without hyphens. It’s clear in hindsight that, as you suggest, post-traumatic was hyphenated in that term (and not in the list of words formed with post-) for a reason, one that had nothing to do with consecutive t’s. (The latest iteration of Merriam-Webster, as of November 4, 2025, now hyphenates post-traumatic as a standalone term also.)
But the dictionary doesn’t do en dashes,* and in post-traumatic stress disorder, no one else seems to either (not even Wikipedia, which tends to feature a lot of en dashes compared with other publications). Instead, we’d advise saving your en dashes for more established uses (see CMOS 6.82–90—especially 6.86, on en dashes with compound adjectives).
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* The hyphenated main entries in printed editions of Merriam-Webster do feature en dashes rather than hyphens, but that’s presumably for the sake of legibility in very small type and therefore doesn’t count (see also this related Q&A).
[This answer relies on the 18th edition of CMOS (2024) unless otherwise noted.]
Q. With the new rule for the en dash and personal names (CMOS 6.85), does that mean a city like Winston-Salem will be spelled with an en dash now?
A. That’s a good question, but the new rule does not extend to a place-name like Winston-Salem. Nor would it extend to a name like Merriam-Webster (the dictionary publisher). Such names are like the hyphenated surname Newton-John in the name Olivia Newton-John. Though each of those three names (of the city, the publisher, and the person) combines two names, they’re each considered to be a single hyphenated unit.
The en dash in a term like “Epstein–Barr virus” or “Ali–Frazier fight,” by contrast, is supposed to help clarify that something (as a virus or a fight) is being attributed to two people rather than just one. A Winston-Salem virus or Winston-Salem fight, on the other hand, would be a virus or a fight named for a single city in North Carolina—one that happens to have a double-barreled (and hyphenated) name.
Note, however, that the names of some places would get an en dash in Chicago style: for example, Minneapolis–Saint Paul, where the dash connects to an open compound (see also CMOS 6.86).
[This answer relies on the 18th edition of CMOS (2024) unless otherwise noted.]
Q. What is Chicago style for elongated words: huuuuge or h-u-u-u-u-ge? Thank you.
A. Chicago doesn’t have a style for such words. But maybe you’ve noticed that some people write, for example, likeeee or cuteeee. Those texting-era spellings don’t make much sense when spoken: Which part is drawn out, the final consonant or the eeee? Within a text, however, they suggest that the writer is using the last letter as an exclamation point, tapping it repeatedly for emphasis or to show enthusiasm. Hyphens would ruin this effect (cute-e-e-e?).
You could point then to texting as a precedent and repeat the letter u (as in your first version, huuuuge). It’s cleaner on the page (or screen) than the one with all the hyphens, and the intended pronunciation is obvious. Or you could go with hugeeee—but only if your goal is to use (or to mimic) the textspeak repetition of the final letter noted above. Then the e’s at the end might seem normal (That’s hugeeee!!!).
For the use of hyphens to suggest stuttering, see CMOS 12.44.
[This answer relies on the 18th edition of CMOS (2024) unless otherwise noted.]
Q. In the following sentence, is it correct to use an en dash after 25 but a hyphen after 30? “The report referred to a 25– to 30-year-old oak tree on the perimeter of the parking lot.”
A. It looks as if you’re trying to extend the logic behind expressions like “pre–Civil War,” where the idea is that an en dash, which is longer than a hyphen, bridges the space in “Civil War” to apply the prefix “pre” to both words in that phrase.
But Chicago style for your example would be to write “a 25-to-30-year-old oak tree,” with four hyphens. Only in the case of two different ages rather than a range would we recommend something like what you’ve written, but with a suspended hyphen instead of an en dash: “a 25- or 30-year-old oak tree”—which is short for “a 25-year-old or 30-year-old oak tree.” (See CMOS 7.96, section 1, under “age terms.”)
In each of those examples, the hyphen in “25-” is like the one in “30-”; an en dash rather than a hyphen after the first number might look like a mistake, and it wouldn’t necessarily make the expression any clearer. For more on suspended hyphens, see CMOS 7.95.
[This answer relies on the 18th edition of CMOS (2024) unless otherwise noted.]
Q. While The Chicago Manual of Style still supports a no-hyphen version of “up to date” when not before a noun, Merriam-Webster appears to support using hyphens in all cases. I am not sure which to advise my clients to use.
A. When Merriam-Webster and CMOS disagree relative to hyphenation, follow CMOS. Because CMOS says specifically that “up to date” remains open after a noun—an up-to-date solution but his equipment was up to date (see the hyphenation guide at CMOS 7.96, under “phrases, adjectival”)—that’s what you should advise.
Keep in mind that Chicago favors a spare hyphenation style. What this often means in practice is that any compound adjective that follows the noun it modifies (i.e., instead of directly preceding it) can usually be left open. There are only a few adjective phrases that retain hyphens in any position—among them all-consuming and high-spirited—as described in CMOS 7.92.
But those are exceptions. In general, documents that include relatively few hyphens in compound adjectives after a noun will be the ones that are the most up to date as far as Chicago style is concerned (up to and including the 18th edition).
[This answer relies on the 18th edition of CMOS (2024) unless otherwise noted.]
Q. I’m proofreading a book that was previously published in the UK for forthcoming US publication. The hyphenation of “century” compounds using BCE/CE preceding a noun is inconsistent throughout. Examples: “A first-century-CE graffito from a wall in Pompeii”; “A second-century BCE satire.” My inclination, guided by CMOS 7.94 (on multiple hyphens), is to follow the second example, without a hyphen before BCE/CE, which is also how the UK edition was styled. I can’t seem to find any CMOS guidance that specifically addresses this issue, though. Is my inclination sound? Many thanks for any help.
A. We agree with your inclination, which also happens to be supported by Chicago’s recommendation to omit hyphens in compound modifiers consisting of a number plus an abbreviation, as in the 33 m distance (see CMOS 7.96, sec. 1, under “number + abbreviation”). That example isn’t perfectly analogous to a first-century CE graffito, but it’s close enough.
[This answer relies on the 18th edition of CMOS (2024) unless otherwise noted.]
Q. Hi. I have a question regarding the use of the em dash between two independent sentences (as in CMOS 6.91, last example). I understand that the dash can be used in place of a colon when introducing a list; however, when it is used to separate two independent sentences, as a semicolon would be used, it reads as a comma splice (as in your example): “The number of new cases has been declining—last week’s daily average was the lowest since January.” Wouldn’t a semicolon or period be better than an em dash in that example?
A. You’re right that a semicolon or a period might be better than a dash in that example. But we wanted our examples to show that a dash really can be used in place of just about any mark of punctuation. And don’t worry about creating a comma splice—only commas can do that.
It might help to show the same sentence but with parentheses:
The number of new cases has been declining (last week’s daily average was the lowest since January).
If you agree that those parentheses work, then consider that dashes and parentheses are usually interchangeable (though parentheses are not as abrupt as dashes, and they always come in pairs; see also CMOS 6.101).
But that doesn’t mean anything goes. Because dashes are so flexible, they tend to be overused. When in doubt, edit them out.
[This answer relies on the 18th edition of CMOS (2024) unless otherwise noted.]
Q. Is it acceptable to hyphenate an approximate measurement? Here are some examples: “I boxed up two-hundred-something widgets.” “It will take five-or-so days to complete.” “I need two-and-a-half months for a project of that scope.” (A half month is not a specific number of days.) Thank you for your help!
A. Hyphenation isn’t normally related to how exact a measurement might be. In your three examples, we’d apply no hyphens but one en dash (for the widgets):
I boxed up two hundred–something widgets.
It will take five or so days to complete.
I need two and a half months for a project of that scope.
According to Merriam-Webster, the word something in the sense you’ve used it—“some indeterminate amount more than a specified number”—is a combining form that connects to other words with a hyphen, as in “twenty-something years old.” When joined to the open compound “two hundred,” it gets an en dash in Chicago style (see CMOS 6.86). The other expressions of approximation in the examples above—“or so” and “and a half”—are ordinary phrases that don’t require hyphens.
[This answer relies on the 18th edition of CMOS (2024) unless otherwise noted.]
Q. Merriam-Webster lists “fact-check” as a verb (with a hyphen). But what about when it’s used as a noun—as in, “Oh no, not another fact check!” My guess is that it’s not hyphenated, but I would like to see an entry on this. Thank you.
A. We agree with your guess, so we turned to the OED for confirmation. That dictionary includes an entry for “fact-check” as a verb (with a hyphen) and another for “fact check” as a noun (no hyphen).
Interestingly, the noun and verb forms both first appeared in 1965, but in separate publications (according to the quotations in the OED entries). The verb appeared in a classified ad in the Chicago Tribune on February 7: “Loop encyclopedia needs science-oriented person to fact-check manuscripts”; the noun showed up in the University of Pennsylvania Law Review (vol. 113, no. 8, p. 1175): “Where more than a superficial fact check is required, the type of data typically provided in a presentence report is what might be desired.”
That job opening in the Loop sounds intriguing. If we had more time, we might do a fact check to find out which encyclopedia that was.
[This answer relies on the 17th edition of CMOS (2017) unless otherwise noted.]
Q. Should “cotton gin maker” have a hyphen? Does “cotton gin” here serve as an adjective, necessitating the hyphen? I’ve consulted CMOS and am still not quite sure. Thanks!
A. Good question! According to the hyphenation guide at CMOS 7.89 (see section 2, under “noun + noun, single function”), when a phrase like “cotton gin,” in which one noun (“cotton”) modifies another noun (“gin”), is used to modify a third noun (“cotton gin” modifies “maker”), the phrase would normally be hyphenated: cotton-gin maker.
That said, some editors would omit the hyphen. Not only is “cotton gin” entered as an unhyphenated noun in Merriam-Webster (with no adjective form, hyphenated or not, listed with it), but unless the surrounding context isn’t obviously relevant to cotton gins as opposed to some kind of process for making gin with cotton (whatever that would be), there isn’t much chance of confusion without the hyphen.
In sum, add the hyphen to be on the safe side, knowing that you can instead leave it out if that’s your strong preference (provided you’re consistent). In other words, this is a gray area (like the spelling of gray).
[This answer relies on the 17th edition of CMOS (2017) unless otherwise noted.]