The DICT Development Group

  179 Moby Thesaurus words for "stupid":
     Boeotian, absurd, addled, apish, asinine, backward, balmy, barmy,
     batty, beef-brained, beef-witted, beetleheaded, befooled, beguiled,
     besotted, blear-eyed, blear-witted, block, blockheaded, blockish,
     boneheaded, bootless, boring, bovine, brainless, brute, brutish,
     buffoonish, chuckleheaded, chumpish, clod, cloddish, cockamamie,
     cockeyed, cowish, crass, crazy, credulous, cretinous, cuckoo,
     daffy, daft, dazed, dense, dim, dim-witted, dimwit, dizzy, dolt,
     doltish, donkey, dope, dopey, doting, dozy, dull, dull-witted,
     dullard, dullhead, dumb, dumb cluck, dumbbell, dummkopf, dummy,
     dunce, duncical, duncish, empty-headed, fat, fatheaded, fatuitous,
     fatuous, flaky, fond, fool, foolhardy, foolheaded, foolish,
     frivolous, fuddled, futile, gaga, goofy, goosey, gowk, gross,
     gulled, half-assed, half-baked, half-witted, ho-hum, humdrum,
     idiot, idiotic, ignoramus, ill-advised, imbecile, imbecilic, inane,
     ineducable, inept, infatuated, insane, insipid, irrational,
     irresponsible, jerky, jobbernowl, klutzy, kooky, lackwit,
     lamebrain, laughable, lightweight, looby, loon, loony, ludicrous,
     lumbering, lumpish, mad, maudlin, mindless, monotonous, moron,
     moronic, niais, nincompoop, ninny, ninnyhammer, nitwit, noddy,
     nonsensical, numskulled, nutty, oafish, obtuse, opaque, pinhead,
     prosaic, put, retarded, ridiculous, risible, sappy, scatterbrained,
     screwy, senseless, sentimental, silly, simple, simpleton, slow,
     slow-witted, sluggish, sottish, stolid, subnormal, tedious, thick,
     thick-witted, thickheaded, thickwit, thoughtless, tiresome, torpid,
     unimaginative, uninspired, unintelligent, uninteresting,
     unteachable, vacuous, vapid, wacky, weak-minded, wet, witless,
     witling, wrongheaded