Q. I understand CMOS’s position on this, but I need help with my argument. Our company’s acronym is singular and ends in an S, just like CMOS. I want to write it with an apostrophe s when needing possession, but others want to use only the apostrophe, as in CMOS’. I need help with my argument with my boss. Thank you. Answer » A. Unlike a personal name that ends in an s (e.g., Harris), an all-caps acronym like CMOS (pronounced SEE-moss) doesn’t even have the appearance of a plural; the s that signals a plural ending is normally lowercase. (A company with two chief marketing officers would have two CMOs, not two CMOS.) So even if you followed a style that prefers Harris’ reputation to Harris’s reputation, an expression like TASS’ headquarters (for the Russian news agency) would risk being misread, whereas TASS’s headquarters is perfectly clear. The same could be said for an initialism, which is pronounced as a series of letters: CBS’s newscasts is more clearly possessive than CBS’ newscasts. We sincerely hope you manage to win your argument (and keep your s). « Close

Q. Good morning! I want to know, should it be “farmers’ market” or “farmers market”? I see everything out there, including “farmer’s market.” Anyway, just a seasonal curiosity for you all! Answer » A. We prefer “farmers’ market.” In Merriam-Webster, “farmers market,” “farmers’ market,” and “farmer’s market” are all listed, in that order, as equal variants (separated by “or”). M-W is descriptive—its entries reflect what it finds in published sources. Clearly, the lexicographers at M-W are seeing what you’re seeing. Normally Chicago would advise opting for the first-listed term in M-W. But for terms like “farmers’ market” that denote group ownership or participation, opting for the plural possessive will help you to maintain editorial consistency across like terms. For more advice, see CMOS 7.27. « Close

Q. In reply to the question of whether it should be “the Rangers hockey game” or “the Rangers’ hockey game,” you basically said that both are acceptable but the former is slightly preferred. I’d like to point out two things that make the former even more preferable. (1) The Rangers play more than one hockey game (and more than one per season), so you can never attend the Rangers hockey game, but only a Rangers hockey game. (2) A hockey game isn’t really a possession of the Rangers like their rink, but is rather an event (something incorporeal) that is merely highly associated with the Rangers, and whose association with the Rangers is only 50 percent (the other 50 percent of the association is with the opposing team). Answer » A. Thank you for these thoughts! Let me point out a few things in reply. (1) Of course you can attend “the Rangers hockey game.” If I say, “Last night we went to the Rangers hockey game,” I’m referring to the game that was held last night. (2) The genitive indicated by apostrophe + s serves many purposes besides literal possession. Please see CMOS 5.20 for examples. (3) You might have misread our answer; in fact, CMOS 7.27 says, “If in doubt, choose the plural possessive.” « Close

Q. Should the possessive form of Los Angeles include the extra s? As a Spanish term, the city’s name is a singular noun, plural in form, but if we consider it fully anglicized, does it then count as a regular singular? Or does the plural form carry through? Answer » A. It’s true that city names that include a plural word in English can drop the extra s when forming the possessive: Twin Groves’ population. But city names are by default singular (Twin Groves is a small city), and a guideline for styling non-English names in English should not depend on a writer’s knowledge of their meaning in the original language. Thus the possessive of Los Angeles in Chicago style follows the guidelines for singular possessives in English: Los Angeles’s. « Close

Q. I’m on a team editing kids’ textbooks. One book includes a poster showing shapes (circle, square, triangle). Should this be referred to as a shapes poster? Is it an example of the genitive case 4 (at CMOS 5.20), requiring an apostrophe: shapes’ poster? If not, is it a temporary compound noun? Could it be written either way, based on personal preference? Does genitive case 7 help at all? A poster of shapes = shapes’ poster. Answer » A. No apostrophe is needed because shapes is an attributive noun. “A shapes poster” is grammatically akin to “a commodities trader” and “a weapons dump” in containing a noun (singular or plural) that is used attributively as an adjective (shapes, commodities, weapons). You can read about attributive nouns at CMOS 5.24, “Nouns as Adjectives.” « Close

Q. I think there’s a contradiction in your examples of the correct use of apostrophes. CMOS 7.20 states that in the case of a place-name ending with “s,” the “s’s” formation is not used; e.g., the United States’. However, 7.17 uses Kansas’s as an example of proper usage. Is that correct? Answer » A. Kansas’s is indeed correct. The tricky part of paragraph 7.20 says to omit the extra s from place-names ending in s “with a plural form,” and Kansas doesn’t qualify as a plural form, even though it happens to end in s (singular Kansas; plural Kansases; there is no singular Kansa). The form of States, in contrast, is plural (singular state; plural states), even though the proper noun United States is singular. Plural forms ending in s take an apostrophe without a second s, whether the word is singular or plural: the United States’ reputation. But singular forms like Kansas take that second s, and thus it’s Kansas’s. « Close

Q. When referring to the left or right side of a vehicle, is the adjective possessive or attributive? Is the proper form “driver’s-side door” or “driver-side door”? Answer » A. You get to decide! Both are fine. « Close

Q. This question has probably been asked before, but at work we are updating the human resources manual and nobody seems to know the answer. Is the apostrophe necessary in “two weeks’ notice” and “three days’ sick leave”? We will really appreciate your advice. Answer » A. Yes, it has been asked before! Luckily for you, we are the soul of patience. The apostrophe is necessary, since those phrases express a type of possessive. Please see CMOS 7.25. « Close

Q. For our work editing projects, we have had a long-standing debate over the wording “renters insurance” (as a concept). There seems to be no industry standard with regard to using an apostrophe. Which should it be? Renters’ insurance, renter’s insurance, renters insurance. Answer » A. All those forms are fine, but Chicago prefers the plural possessive. Please see CMOS 7.27. « Close