Editing to a particular style manual might mean hewing to older spellings. Dictionary entries always lag the changing language. There is only so much a limited staff of diligent drudges can update in a given period.
If we strictly follow a style guide and therefore its preferred dictionary, we can’t always spell something just because we think it’s the way it ought to be spelled. For consistency, we want to spell a word the way it appears in the correct dictionary’s last printing or electronic update.
This is why, until this year, if we allowed goodbye instead of good-bye in a paper edited in Chicago style, we were doing it wrong.
Goodbye and the issue of that hyphen are now closed thanks to a recent update of the dictionary at Merriam-Webster.com (but if your style gurus insist on the paper edition, sorry, it’s still good-bye).
Here are a few other words whose usage dictionaries may not have kept up with.
Merriam-Webster’s Collegiate Dictionary, 11th Edition, hyphenates spin-off as a noun and lists it as two words when used as a verb. As the preferred dictionary of the Chicago Manual of Style and most other style guides, the Collegiate’s spelling takes precedence for many edited documents. But the Associated Press Stylebook agrees with its preferred dictionary, Webster’s New World Fifth College Edition, and goes without the hyphen—spinoff.
So in Chicago style, Young Sheldon is a spin-off of The Big Bang Theory; in AP style, it’s a spinoff.
A new business venture is a startup in the AP Stylebook, which disagrees with its preferred dictionary. Webster’s New World still renders it start-up as the first spelling. In M-W Collegiate, the spelling is still start-up, so we keep the hyphen in much edited text.
The hyphen stays in breast-feeding in Chicago and AP styles, even though breastfeeding seems to be much more common, even in edited text.
The Harlem Globe Trotters closed up Globetrotters in the early 1930s, just a few years after dropping Chicago and adding Harlem to their name. But if you are editing in Chicago or AP style, the generic form is still globe-trotter (and globe-trotting). The American Heritage Dictionary and the New Oxford American Dictionary don’t suggest the hyphen.
Everyone seems OK with smartphone, but M-W Collegiate doesn’t yet recognize the one-word cellphone. AP Stylebook closed it up in 2011.
The one-word carpool is fairly well accepted as a verb, and it’s increasingly rendered that way as a noun. But Chicago and AP agree for now that the noun version is car pool. The American Heritage Dictionary and the New Oxford American Dictionary disagree with those style guides.