nutcase

1 a person judged to be legally or medically insane <some nutcase was arrested for sending the threatening letters to the White House> Synonyms bug, crackbrain, crazy, fool, fruitcake, head case, loon, loony, maniac, nut, lunatic, nutter [British slang], psycho, psychopath, sickie, sicko, wacko (also whacko)Related Words madman, madwoman; abnormal, deviant; manic-depressive, monomaniac, mythomaniac, neurotic, obsessive, obsessive-compulsive, paranoid, psychoneurotic, psychotic, schizo, schizoid, schizophrene, schizophrenic, sociopath; character, codger, crack, crackpot, crank, eccentric, fantastic (also fantastical), flake, kook, oddball, oddity, original, quiz, screwball, tyke (also tike) [chiefly British], weirdo, zany; case, patient

2 a person of odd or whimsical habits <around the condo complex she's known as the nutcase who consistently ignores the rules> Synonyms character, codger, crack, crackbrain, crackpot, crank, flake, fruitcake, head case, kook, nut, eccentric, nutter [British slang], oddball, oddity, original, quiz, screwball, weirdo, zanyRelated Words bohemian, maverick, nonconformist, quixote; coot, geezer; curio, rarity; freak; fantast, fantasticoNear Antonyms conformer, conformist, follower, sheep

3 a person who lacks good sense or judgment <only a nutcase would try to accelerate a campfire by dousing it with gasoline> Synonyms berk [British], booby, charlie (also charley) [British], cuckoo, ding-a-ling, dingbat, ding-dong, dipstick, doofus [slang], featherhead, git [British], goose, half-wit, jackass, lunatic, mooncalf, nincompoop, ninny, ninnyhammer, nit [chiefly British], nitwit, nut, fool, simp, simpleton, turkey, yo-yoRelated Words daredevil; madman, madwoman; airhead, birdbrain, blockhead, cretin, dodo, dolt, donkey, dope, dork [slang], dumbbell, dummy, dunce, fathead, gander, goon, half-wit, idiot, ignoramus, imbecile, know-nothing, knucklehead, moron, numskull (or numbskull), pinhead, schlub (also shlub) [slang], schlump [slang], schnook [slang], stock; featherbrain, scatterbrain; butt, dupe, laughingstock, mockery, monkey; chump, loser, schlemiel (also shlemiel); character, codger, crackbrain, crackpot, crank, kook, oddball, screwball, weirdoNear Antonyms sage, thinker; brain, genius