English English language Expression Grammar Usage

The third degree

Q: In your 2012 post about “master’s degree,” you say the plural is “master’s degrees,” but you don’t say why. I can see why one person can have three “master’s degrees” since he is the master in question. But what if three people have them? Don’t these become “masters’ degrees”?

A: No, the plural is still “master’s degrees,” no matter how many scholars have them.

“When you pluralize the phrase as a whole,” we wrote in 2012, “only ‘degree’ gets the plural ‘s.’ The adjective ‘master’s’ doesn’t itself become plural.”

Now for the “why”!

Many people would call “master’s” here a “possessive,” and therein lies the problem. A better term would be “genitive,” a case that includes the possessive as well as many other kinds of relationship, as we’ve written before on our blog.

The compound “master’s degree” is an excellent example of the genitive at work. It indicates an adjectival relationship between “master’s” and “degree.” It describes the type of degree, not who possesses it.

So whether you’re talking about several degrees or only one, several scholars or only one, the adjectival part of the noun phrase stays the same: “master’s.”

The Cambridge Grammar of the English Language, for example, would label “master’s” an “attributive genitive” or “descriptive genitive.”

In a section devoted to these constructions, Cambridge uses the example “two bachelor’s degrees.” (Note the singular “bachelor’s” and the plural “degrees.”)

In many fixed expressions, the genitive modifier doesn’t change even though the expression as a whole has both singular and plural forms.

Besides “bachelor’s degrees,” Cambridge uses the example “fisherman’s cottages,” which it says denotes “cottages typical of those lived in by a fisherman.”

We can think of some other genitive modifiers that are singular though the noun they modify can go either way: “summer’s day” and “summer’s days” … “busman’s holiday” and “busman’s holidays” … “boatswain’s mate” and “boatswain’s mates” … “plumber’s wrench” and “plumber’s wrenches” … “this Mother’s Day” and “three Mother’s Days in a row.”

By the same token, some genitive modifiers are plural and stay that way, though the noun they modify goes both ways.

Examples: “old people’s home” and “old people’s homes” … “girls’ school” and “girls’ schools” … “women’s soccer team” and “women’s soccer teams” … “boys’ club” and “boys’ clubs” … “farmers’ market” and “farmers’ markets.”

Of course, where there’s actual possession and the modifier isn’t merely descriptive of a kind or type, the possessive adjective changes in number (as with “the book’s jacket” and “the books’ jackets”).

But add one “master’s degree” with another, and you have “two master’s degrees.” For another source, we turned to Words Into Type,  which is widely used by journalists and other writers. It has this to say:

“A substantive phrase containing a possessive—master’s degree, for example—is changed to the plural by adding s to the second word.” The examples given: “master’s degrees, debtor’s prisons.”

A final note about the apostrophe. Standard dictionaries, as well as The Chicago Manual of Style (17th ed., section 8.29), use the apostrophe in “master’s degree.” But as we wrote in 2008, when a plural noun is used as the modifier, some organizations don’t use an apostrophe.

This is why one program will call itself a “Writers’ Workshop” while another is a “Writers Workshop.” This also accounts for such names as “Publishers Weekly,” “Diners Club,” and “Department of Veterans Affairs,” as the Chicago Manual points out.

But the manual recommends (section 7.27) that the apostrophe be dropped “only in proper names (often corporate names) that do not officially include one.”

So it recommends retaining the apostrophe in compounds like “boys’ clubs,” “consumers’ group,” “taxpayers’ associations,” “farmers’ market,” and so on.

[NOTE: This post was updated on March 24, 2018, to match wording in a later edition of the Chicago Manual.]

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