Something is meretricious if it seems attractive and flashy but really isn't. The attraction may be false or it may be vulgar and showy. It can apply to people, to clothing, or to television commercials, for example. It can even refer to showy, misleading arguments, such as the ones we hear during political campaigns (but only from the other party, of course). It's an insult that sounds like a compliment, so you might be able to use it against someone with a small vocabulary. It sounds like a compliment because it sounds like the positive word merit, to which it is actually closely related. The root is the Latin word meretrix, meaning a prostitute, and that word comes from mereri, "to earn," which is also the root of the word merit. Here's a surprising related word. There was an earth-colored spice the Romans valued for its medicinal properties. They called it terra merita, meaning "earth of merit." After passing through Medieval French and Old English and then finally into modern English, that name had become distorted into "turmeric" - a spice whose attractions are quite genuine and thus the opposite of meretricious.
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