a convention in the card game of cribbage in which a player scores points overlooked by an opponent.
2.
a game of dominoes, in which any player who can make the sum of two ends of the line equal five or a multiple of five adds the number so made to his or her score.
3.
British Slang.a fool.
Origin: 1850–55; probably special use of proper name; def. 3 by association with mug