The Oxford Thesaurus An A-Z Dictionary of Synonyms - gagэn.

1) joke, witticism, jest, quip, pun, gibe, Colloq wisecrack, Slang crack: He told some gags but nobody found them funny. 2) practical joke, hoax, prank, trick, Colloq fast one: For a gag, we put a snake in the sergeant's bed.