The Grammarphobia Blog

Caffeine content

Q: Why is “teacup” one word but “coffee cup” two words?

A: Although “teacup” is usually written as one word and “coffee cup” as two, they’re sometimes spelled the same way. The Oxford English Dictionary, for example, hyphenates both: “tea-cup” and “coffee-cup.”

We checked six standard dictionaries—three American and three British—and all of them listed “teacup” as one word. Only one had an entry for the cup used to drink java, and listed it as two words: “coffee cup.”

So why is “teacup” usually one word and “coffee cup” two? The answer may lie in the dearth of dictionary entries for the container used to drink coffee.

Perhaps lexicographers feel that “teacup” is popular enough to be listed as a single word while “coffee cup” isn’t popular enough to get an entry.

In googling the two terms, we got five times as many hits for “teacup” as we did for “coffee cup.” (The “coffee cup” results included the hyphenated version.)

However, both “teacup” and “coffee cup” are very popular, with many millions of hits apiece. So perhaps the answer lies elsewhere.

Interestingly, many dictionaries that ignore “coffee cup” have single-word entries for less popular terms like “coffeecake,” “coffeemaker,” and “coffeepot.”

Words often begin life as two separate terms (like “try out”), then become hyphenated (“try-out”), and finally lose their hyphens as they become more common (“tryout”). But “teacup” and “coffee cup” appear to be exceptions that prove the rule.

The earliest citation for “teacup” in the OED (from a play by William Congreve that premiered in 1700) is a hyphenated version: “Let Mahometan Fools … be damn’d over Tea-Cups and Coffee.”

A one-worder showed up 14 years later in the writings of Joseph Addison: “The fashion of the teacup … has run through a wonderful variety of colour, shape, and size.”

As for “coffee cup,” it began life as two words connected with a hyphen, according to OED citations, and ended up as two words, minus the hyphen.

The OED’s first published reference for the usage is from a 1782 book by Horace Walpole about English painting: “I have a coffee-cup of his ware.”

But more recent citations are two worded and hyphen-free. Here’s a colorful one from what appears to be a Vanity Fair review of the 1999 film Office Space:

The fiefdom’s key rat fink and enforcer is a supervisor named Bill Lumbergh (Gary Cole), a walking vanity plate who patrols the tick-tack-toe cubicles, coffee cup in hand, acting as if he just happened to be dropping by.”

Sorry we can’t be more helpful. We drink coffee as well as tea, and we use the same containers for both. What do we call them? The small ones are “cups” and the big ones are “mugs.”

Check out our books about the English language