Synonyms and related words :
absurd, ass, balmy, born fool, buffoon, clown, crazy, donkey, doodle, egregious ass, fantastic, figure of fun, fool, harebrained, idiot, ignoramus, imbecile, insane, jackass, jerk, loony, lunatic, milksop, mooncalf, nincompoop, ninny, perfect fool, preposterous, schmuck, silly, softhead, sop, stupid ass, zany