Origin and history of weasel

small, carnivorous mammal proverbial for its cunning, Middle English wesel, from Old English weosule, wesle "weasel," from Proto-Germanic *wisulon (source also of Old Norse visla, Middle Dutch wesel, Dutch wezel, Old High German wisula, German Wiesel).

This is of obscure origin, said in Watkins to be probably related to Proto-Germanic *wisand- "bison" (see bison), with a base sense of "stinking animal," because both animals have a foul, musky smell (compare Latin vissio "stench").

A John Wesilheued ("John Weaselhead") turns up on the Lincolnshire Assize Rolls for 1384, but the surname seems not to have endured. Related: Weaselly.

"deprive (a word or phrase) of its meaning," 1900, from weasel (n.); so used because the weasel sucks out the contents of eggs, leaving the shell intact. Both this and weasel-word are first attested in "The Stained-Glass Political Platform," a short story by Stewart Chaplin, printed in Century Magazine, June 1900:

"Why, weasel words are words that suck all the life out of the words next to them, just as a weasel sucks an egg and leaves the shell. If you heft the egg afterward it's as light as a feather, and not very filling when you're hungry; but a basketful of them would make quite a show, and would bamboozle the unwary."

An awkward image but a catchy phrase, picked up at once in American political slang along with the verb.

The sense of "extricate oneself (from a difficult place) like a weasel" is recorded by 1925, a separate evolution; that of "evade and equivocate" is by 1956, perhaps a mix of both. Related: Weaseled; weaseling.