12
non compos mentis(expression, adjective, idiom, law, unstable)
12
wacky(adjective, wrong, slang, unusual, wild)
11
bonkers(adjective, informal, silly, foolish, crazy)
11
delirious(adjective, upset, silly, crazy, mad)
11
loco(adjective, slang, insane, sane)
11
mental(adjective, simple, silly, foolish, mad)
11
of unsound mind(expression, adjective, idiom, silly, mad)
10
dotty(adjective, wrong, strange, silly, crazy)
10
brainsick(adjective, wrong, crazy, confused, insane)
10
daffy(adjective, simple, informal, silly, foolish)
10
screwy(adjective, slang, wild, silly, foolish)
10
sick(adjective, ill, unhealthy, frail)
10
wild(adjective, wrong, silly, foolish, stupid)
9
foolish(adjective, wrong, wild, strange, silly)
9
hysterical(adjective, upset, mad, insane, irrational)
9
maniac(adjective, violent, crazy, fierce, insane)
9
moonstruck(adjective, silly, foolish, stupid, mad)
9
psycho(adjective, silly, foolish, crazy, mad)
9
unsound(adjective, simple, foolish, crazy, unstable)
8
barmy(adjective, silly, foolish, crazy, mad)
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APASmart Define. (2015). demented thesaurus. Retrieved September 22, 2026, from https://smartdefine.org/demented/thesaurus/synonyms
ChicagoSmart Define. 2015. "demented thesaurus" https://smartdefine.org/demented/thesaurus/synonyms (accessed September 22, 2026).
HarvardSmart Define 2015, demented thesaurus, Smart Define, viewed 22 September, 2026, <https://smartdefine.org/demented/thesaurus/synonyms>.
MLASmart Define. "demented thesaurus" 17 July 2015. Web. 22 September 2026. <https://smartdefine.org/demented/thesaurus/synonyms>