Thesaurus

insane

adjective

Synonyms and Antonyms of INSANE

1
having or showing a very abnormal or sick state of mind <only an insane person would intentionally jump off a skyscraper>
Synonyms balmy, barmy [chiefly British], bats, batty, bedlam, bonkers, brainsick, bughouse [slang], certifiable, crackbrained, cracked, crackers, crackpot, cranky [dialect], crazed, crazy, cuckoo, daffy, daft, demented, deranged, fruity [slang], gaga, haywire, kooky (also kookie), loco [slang], loony (also looney), loony tunes (or looney tunes), lunatic, mad, maniacal (also maniac), mental, meshuga (or meshugge also meshugah or meshuggah), moonstruck, non compos mentis, nuts, nutty, psycho, psychotic, scatty [chiefly British], screwy, unbalanced, unhinged, unsound, wacko (also whacko), wacky (also whacky), wud [chiefly Scottish]
Phrases around the bend, off one's gourd, off one's head, off one's rocker, out of one's head (or mind), out to lunch [slang]
2
conceived or made without regard for reason or reality <a completely insane plan to build an opera house in the middle of nowhere>

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