A word that sparkles by its acid?

I made a minor discovery the other day. A word that I had seen in print many times, and of which I had formed a vague impression, as of a neighbor one encounters only on take-out-the-trash day, actually means something very different from what I'd thought.

The word is coruscating and it means "sparkling." It comes from a Latin verb meaning to vibrate or to glitter.

The American Heritage Dictionary defines coruscate, the verb, thus: "To give forth flashes of light; sparkle and glitter: diamonds coruscating in the candlelight," or alternatively, "To exhibit sparkling virtuosity: a flutist whose music coruscated throughout the concert hall."

I would have guessed from the sound symbolism, though, that "coruscating" involves using some dreadful chemical to clear barnacles from a ship. And a little research shows I was not alone in this.

A writer on a website of the University of Hull, in England, notes: "Figuratively," coruscating "is used to mean 'very clever', 'able', 'vivid'– using the same sort of image as in 'brilliant' and, at its most basic, 'bright.' So to say that someone coruscates, or that he has a coruscating wit, is a compliment."

This writer goes on to say, however, that people often use the word to mean "very hostile" or "savage," and suggests that the word they are reaching for but not quite finding is excoriate. This 50-cent word means literally "to take the skin off (someone)," or, to put it in four-letter Anglo-Saxon, "to flay."

Corrosive may be another word writers have in mind when they use the nonsparkly coruscating, our friend in Hull suggests. This makes me feel I wasn't so far off with my barnacle idea.

And now it's time to bring in another character in this microdrama: wit.

Wit is such a frequent companion of coruscating that the two words form a set phrase. A quick Google search shows 93,800 hits for "coruscating," and about 16,000 for the phrase "coruscating wit." Professional lexicographers will have their own views on this, but it looks to me like the linguistic equivalent of going out every Saturday night with the same guy.

One online dictionary translates "coruscating wit" into Hungarian – as a set phrase. Ah, but in what sense? The truly sparkly? Or the acidic? The same question can be asked of any number of writers on the Web.

Insofar as many wits are more interested in skewering than in sparkling, "coruscating" may seem higher praise if it means the former rather than the latter – and so the acidic meaning may eventually shed the label of malapropism and win a place in dictionaries.

A writer sometimes has to choose a word that may not be absolutely right but will reliably get the message across. There is a little more freedom, though, in some instances with a word or expression that isn't carrying the full load of the meaning of a sentence. It will sparkle, dare I say, for those who get it, but not distract those who don't.

The other side of that coin, though, is that when a 50-cent adjective like coruscating appears in a sentence where it's not essential to meaning, readers are freer to draw their own inferences. In this case, the two meanings are very different, but in any given context, each is likely to be plausible. Readers then use the word themselves in the meaning they have inferred. This is how language changes. Alas.