Dear Word Detective: I've long heard people talk about "souping up" their cars (i.e., tweaking the engine to make it more powerful). I always assumed that this was spelled "suping up," my understanding being that it indicated the car was being made "superior" or "more super" or something like that. Much to my chagrin, however, I've recently learned that I've been spelling it wrong all these years and that it is, in fact, spelled "souped" and not "suped." Well, fine. I don't have a problem acknowledging that I was wrong (although I do think my preferred spelling has a lot going for it). What I haven't been able to find out, however, is where the phrase actually comes from and what, if anything, it has to do with the old Campbell's Cream of Mushroom. -- Barry, via the internet.

I agree that your spelling "souping up" as "suping" makes a lot of sense, and you'll be glad to know that we have the origin of the term to back us up.

In the beginning there was "soup," the Campbell's Cream of Mushroom (yuk) kind, a word which we inherited from the French "soupe," which, like its English relative "sop," originally meant bread soaked in broth. Eventually the broth itself, often with bits of meat and vegetables, came to be known as "soup" in English.

Almost as soon as "soup" appeared on our menu, we began developing figurative meanings for the word, and "soup" has been used as slang for everything from fog to the ocean to a difficult situation ("In the soup"). One particularly interesting use in the context of your question, appearing around 1900, is "soup" as slang for nitroglycerine or other explosives.

"To soup" as a verb originally meant, not surprisingly, to provide someone with soup, but around 1931 "to soup up" appeared, meaning to modify the engine of an aircraft or motor vehicle to increase its power and speed. In part, this use may have been rooted in "soup" as 1930s slang for the stimulants sometimes injected into racehorses to make them run faster. But a more immediate source (and the reason your spelling makes more sense) was probably the fact that the preferred method of "souping up" an engine was to add a "supercharger," a device designed to force additional air into the cylinders and boost power. It is also possible that the simple adjective "super," as you guessed, may have figured into "souping up."