Full Idea
Most people know how to use the word "Amen", but they do not know what it means.
Gist of Idea
Most people know how to use the word "Amen", but they do not know what it means
Source
David E. Cooper (Philosophy and the Nature of Language [1973], §2.4)
Book Reference
Cooper,David E.: 'Philosophy and the Nature of Language' [Longman 1979], p.39
A Reaction
Personally I find examples like this decisive against the 'use' theory of meaning. Maybe the defence is that the theory works for sentences, and individual words (like passwords) are peripheral.