62 entries under idiom topic. ×

20
of unsound mind(expression, adjective, characteristic, silly)
13
non compos mentis(expression, adjective, law, mad)
10
mentally ill(expression, adjective, mad, sane)
7
not all there(expression, adjective, crazy, unstable)
7
out to lunch(expression, adjective, silly, crazy)
5
off one's rocker(adjective, foolish, ill, sane)
5
round the bend(expression, silly, foolish, mad)
3
not right(expression, crazy, insanity, cuckoo)
3
out of one's mind(adjective, foolish, ill, irrational)
2
around the bend(expression, adjective, wrong, wild)
2
bats in the belfry(expression, silly, foolish, mad)
2
bereft of reason(expression, insanity)
2
beside oneself(expression, adjective, upset, violent)
2
mad as a hatter(expression, adjective, silly, foolish)
2
nutty as fruitcake(expression, silly, foolish, mad)
2
out of it(expression, adjective)
1
mad as a March hare(expression, silly, foolish, mad)
1
at fever pitch
1
bent out of shape(expression, violent, fierce, unreasonable)
1
beyond all reason(expression, silly, foolish, fantastic)
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APASmart Define. (2015). insane thesaurus. Retrieved September 25, 2026, from https://smartdefine.org/insane/thesaurus/synonyms
ChicagoSmart Define. 2015. "insane thesaurus" https://smartdefine.org/insane/thesaurus/synonyms (accessed September 25, 2026).
HarvardSmart Define 2015, insane thesaurus, Smart Define, viewed 25 September, 2026, <https://smartdefine.org/insane/thesaurus/synonyms>.
MLASmart Define. "insane thesaurus" 10 April 2015. Web. 25 September 2026. <https://smartdefine.org/insane/thesaurus/synonyms>