Warning

The phrase "caveat emptor" showed up on The Consumerist, unsurprisingly, since it is a website about consumers and the things of which they ought to be wary, and it occurred to me that I didn't really know where either word came from.

"Emptor", which means "buyer", I could guess at: it seemed pretty clear that it had to have something to do with English "emporium", a place at which one buys things. "Caveat", though, left me at a loss. (In typical English-language fashion, it's become a noun which means "warning".) I couldn't think of anything it might be related to. "Cave"? Obviously not. "Cavil"? Sounds close, or close-ish, but the sense is off ("cavil" means "to unnecessarily find fault with").

Astoundingly, "emporium" and "emptor" are entirely unrelated; absolutely nothing in common at all except a fascinating collision of senses. "Emptor" is from "emere", "to buy", which provided the stem "em-", and the suffix "-tor", "one who" (as in "actor), plus an inserted consonant labelled by phoneticians "intrusive" (also called "excrescent"), which serves to toughen up the sound; "emptor" is easier to say and sounds better than "emtor".

"Emporium", on the other hand, derives from the Greek "emporion", "market", and that in turn comes from "emporos", "merchant", which in turn comes from "poros", "passage, voyage", because of the trips merchants had to take to procure their wares for sale.

And I probably could have guessed where "caveat" comes from if I had remembered that once upon a time, "-u-" and "-v-" were the same letter. "Caveat" is related to "caution"; they both come from Latin "cavere", "to guard against".