FOOLISH

adj. 1 senseless, incautious, imprudent, impolitic, indiscreet, unwise, injudicious, ill-considered, ill-advised, misguided, short-sighted, impetuous, headlong, rash, brash, reckless, hasty, heedless, unwary, foolhardy, thoughtless, mindless Standing under a tree in a thunderstorm is foolish 2 nonsensical, stupid, asinine, inane, silly, fatuous, fatuitous, dim-witted, scatterbrained, hare-brained, crazy, mad, insane, demented, irrational, erratic, unstable, crack-brained, feather-brained, bird-brained, simple-minded, light-headed, muddle-headed, numskulled or numbskulled, addle-pated, rattle-brained, bemused, confused, feeble-minded, moronic, idiotic, imbecilic, halfwitted, dull-witted, slow-witted, witless, brainless, empty-headed, blockheaded, boneheaded, thickheaded, obtuse, stolid, Colloq dumb, balmy or Brit barmy, loony, nuts, nutty, batty, dopey or dopy, soft (in the head), dim, thick, dippy, dotty, dizzy, Brit potty, daft, Slang cuckoo, goofy, screwy, wacky Tracy was foolish to believe him when he said he loved her 3 preposterous, ridiculous, absurd, irrational, illogical, unreasonable, ludicrous, wild They have some foolish idea about building a hotel in Antarctica