Thesaurus
preposterous
adjective
Synonyms and Antonyms of PREPOSTEROUS
1
conceived or made without regard for reason or reality <the idea that extraterrestrials built the pyramids is preposterous>
Related Words implausible, inconceivable, incredible, unbelievable, unimaginable, unthinkable; extravagant, grotesque; bizarro, curious, eccentric, far-out, funny, kinky, kooky (also kookie), odd, outlandish, out-of-the-way, outré, peculiar, quaint, queer, queerish, quirky, screwy, strange, wacky (also whacky), way-out, weird; farcical, laughable, ludicrous, ridiculous; Alice-in-Wonderland, Kafkaesque, nightmarish; dreamlike, surreal
Antonyms realistic, reasonable
2
showing or marked by a lack of good sense or judgment <a preposterous suggestion to go swimming in this freezing weather>
Synonyms absurd, asinine, balmy, brainless, bubbleheaded, cockeyed, crackpot, crazy, cuckoo, daffy, daft, dippy, dotty, fatuous, featherheaded, fool, half-baked, harebrained, half-witted, inept, insane, jerky, kooky (also kookie), loony (also looney), lunatic, lunkheaded, mad, nonsensical, nutty, preposterous, sappy, screwball, senseless, silly, simpleminded, stupid, tomfool, unwise, wacky (also whacky), weak-minded, witless, zany
Related Words airheaded, birdbrained, boobish, brain-dead, chowderheaded, chuckleheaded, clueless, dense, dim, dim-witted, doltish, dopey (also dopy), dorky [slang], dull, dumb, dunderheaded, empty-headed, fatuous, feebleminded, gormless [chiefly British], idiotic (also idiotical), imbecile (or imbecilic), knuckleheaded, lamebrain (or lamebrained), mindless, moronic, oafish, obtuse, opaque, pinheaded, simple, slow, slow-witted, soft, softheaded, thoughtless, thick, thickheaded, unintelligent, vacuous, witless; fallacious, illogical, invalid, irrational, nonrational, surd, unreasonable, unreasoning, unsound, weak; farcical, laughable, ludicrous, ridiculous; notional; buffoonish, clownish; ill-advised, unconsidered, unreasoned
Near Antonyms brainy, bright, clever, intelligent, smart; logical, rational, reasonable, valid; well-advised
3
so foolish or pointless as to be worthy of scornful laughter <the movie thriller had such a preposterous plot that we were on the edge of our seats snickering>
Synonyms absurd, cockamamy (or cockamamie), comical, derisive, derisory, farcical, laughable, ludicrous, pathetic, preposterous, risible, silly
Related Words asinine, brainless, dumb, fatuous, foolish, half-baked, half-witted, harebrained, idiotic (also idiotical), imbecile (or imbecilic), inane, jerky, moronic, nonsensical, simpleminded, stupid, unwise, weak-minded, witless; balmy, cockeyed, crazy, cuckoo, daffy, daft, dotty, insane, kooky (also kookie), loony (also looney), lunatic, mad, nutty, screwball, senseless, wacky (also whacky); fantastic (also fantastical), far-fetched, inconceivable, incredible, unbelievable, unreal, unrealistic, unreasonable; illogical, irrational
Near Antonyms earnest, serious, solemn; believable, conceivable, credible, logical, rational, realistic, reasonable, sensible
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