See jackass in Webster's New World Roget's A-Z Thesaurus II
noun
One deficient in judgment and good sense:
ass, fool, idiot, imbecile, mooncalf, moron, nincompoop, ninny, nitwit, simple, simpleton, softhead, tomfool. (Informal) dope, gander, goose. (Slang) cretin, ding-dong, dip, goof, jerk, nerd, schmo, schmuck, turkey. See ability
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