Malapropism, the mistaken substitution of a word for one with a similar sound but different meaning. Mrs. Malaprop (Latin for "not appropriate") was a character in Sheridan's play, The Rivals, who was fond of saying such things as "He's the very pineapple of kindness." Most malapropisms are unintentional, the result of faulty understanding. I once worked under a principal who got on the intercom to warn students against "conjugating in the halls." Norman Lear's Archie Bunker was the Twentieth Century master of malapropism, extolling Shriner's Conventions as a way to "break up the monogamy," and quoting scripture that "thou shalt not bear falsies to thy neighbor."