You would think that, with all the words we have in our language, it would be perfectly natural to replace a word in an expression with a synonym and have it sound perfectly natural. So, instead of someone saying “I’m going out for a bite to eat,” it should be perfectly natural to say “I’m going out for a nibble to eat.”
But that combination sounds very unnatural. However, if you’re “going out for a nibble,” we’re back in normal territory.
Just as people are often judged by the company they keep, so it is with words.
Some words just go naturally together, or at least are often paired together. So we have a “bunch of carrots,” not a “group of carrots.” You wear a “pair of pants,” not a “set of pants.” You “go home sick”; you don’t “go home unwell.”
These word combinations are called “collocations,” and they can set apart a native speaker or writer from someone who’s not quite fluent.
A collocation is simply when two or more words appear together more frequently than might be expected by chance. Of course there’s a name for that: There’s a name for just about everything in linguistics.
There are, as expected, regional variations of collocations. In the United States, for example, you “take a bath,” while in England you might “have a bath.” In some parts of the country, you “go down the shore,” where in others you “go down to the shore.”
Some collocations are unnecessarily repetitive, like “ATM machine” and “PIN number”–which also suffer from redundant acronym syndrome––or “quiet whisper” and “nodded his head.” Some seem to be incompatible, like “jumbo shrimp” and “pretty ugly.” Some exist for emphasis, like “crystal clear,” “categorically deny,” and, well, “perfectly natural.”
A “collocation” is not the same as an “idiom,” which is a phrase or expression that can’t be understood based solely on the words in it. “Boy, she just opened a can of worms” won’t make sense to anyone who does not know the idiom. A collocation, by contrast, is conventional, understandable by both native and non-native speakers, and more familiar and comfortable to the natives.
Something can be both a collocation, to be read literally, and an idiom, used metaphorically. Depending on the context, telling someone to “break a leg” can be to wish them good luck, or to wish them harm. (“Fracture a leg” sounds less familiar in either context.)
A few “collocations” travel in more rarefied circles, where one word is hardly seen without the other. How often have you seen the word “outage” without its electrifying friend, “power,” close by? (“Outage,” by the way, is an Americanism, and The New York Times Manual of Style and Usage eschews it as “jargon and a euphemism for failure, shutdown or cutoff.”)
If you hear “jangled,” the chances are that “nerves” are not far behind. And unless there’s an animal involved, that “snarl” you just heard was probably brought to the dance by “traffic.”
Words in collocations work together like “peas in a pod.” And that last expression is a collocation, idiom, and a cliché. Yes, it’s familiar, but sometimes familiarity breeds contempt. (Oooh. We did it again!)