I ran across a discussion of the word fink, both as a noun and a verb (and with out). While I recongize the word, it has a slightly archaic sound to me. I think of it as a '50s/'60s slang term, US East Coast in origin. What say all of you?
The OED Online first records it from 1834, meaning weaver: "One of numerous Asiatic or African tropical birds of the family Ploceidae, so called from the elaborately interwoven nests that many of them build. Also more fully weaver-bird."
It had taken on a new meaning by 1903: "A pejorative term of wide application, esp. a. An unpleasant or contemptible person. b. An informer; a detective. c. A strike-breaker."
In 1925 fink was recorded as an intransitive verb: "U.S. slang. To inform on."
Rat fink came on the scene in 1964: "One who is obnoxious or contemptible, esp. (a) an odiously pretentious person; (b) an informer, a traitor. Also attrib. or as adj. Hence as v. trans., to inform on."
Fink out appeared in 1966: "To withdraw or back out from some venture, esp. through cowardice; to ‘chicken out’. Also to fink out on: to fail in (something), to let (someone) down."
Fink and rat fink are terms that I associated with mad magazine in the late '50s and throughout the '60s. Fink is German for finch (families Fringilliadae, Estrildidae, and Emberizidae). I remember the models, having built one or two myself, but always though they were using a common term.