Synonyms and Antonyms of preposterous
- The idea that extraterrestrials built the pyramids is preposterous.
off the wall [slang]
- a preposterous suggestion to go swimming in this freezing weather
absurd, asinine, balmy, brainless, cockeyed, crackpot, crazy, cuckoo, daffy, daft, dippy, dotty, fatuous, featherheaded, fool, foolish, half-baked, half-witted, harebrained, inept, insane, jerky, kooky (also kookie), loony (also looney), lunatic, lunkheaded, mad, nonsensical, nutty, sappy, screwball, senseless, silly, simpleminded, stupid, tomfool, unwise, wacky (also whacky), weak-minded, witless, zany
airheaded, birdbrained, brain-dead, chowderheaded, chuckleheaded, clueless, dense, dim, dim-witted, doltish, dopey (also dopy), dorky [slang], dull, dumb, dunderheaded, empty-headed, fatuous, feebleminded, 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
out to lunch
- The movie thriller had such a preposterous plot that we couldn't help snickering.
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
for the birds
Seen and Heard
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