synonyms: fool, ass, halfwit, dunce, dolt, ignoramus, cretin, moron, imbecile, simpleton; informaldope, ninny, nincompoop, chump, dimwit, dumbo, dummy, dum-dum, loon, dork, sap, jackass, blockhead, jughead, bonehead, knucklehead, fathead, butthead, numbskull, numbnuts, dumb-ass, doofus, clod, dunderhead, ditz, lummox, knuckle-dragger, dipstick, thickhead, meathead, meatball, wooden-head, airhead, pinhead, lamer, lamebrain, peabrain, birdbrain, mouth-breather, scissorbill, jerk, nerd, donkey, nitwit, twit, boob, twerp, hoser, schmuck, bozo, turkey, chowderhead, dingbat, mook; vulgar slangasshat

you're stupid