10
non compos mentis(expression, adjective, idiom, law, mad)
10
touched(adjective, informal, insane, sane)
9
balmy
9
bats
9
daffy(adjective, slang, informal, crazy, mad)
9
fruity(adjective, slang, mad, insane, sane)
9
loopy
9
maniac(adjective, crazy, mad, sick, insane)
9
mentally ill(expression, adjective, idiom, crazy, sick)
9
of unsound mind(expression, adjective, idiom, insane, sane)
9
screwy(adjective, slang, insane, sane)
9
unhinged(adjective, insane)
8
cuckoo(adjective, slang, insane, sane)
8
kooky
8
moonstruck(adjective, insane, sane)
8
psychotic(adjective, crazy, mad, insane, crazed)
7
brainsick(adjective, crazy, sick, insane, sane)
7
buggy(adjective, slang, sane, off, dotty)
7
distraught(adjective, crazy, sick, insane, sane)
7
irrational(adjective, crazy, mad, insane, distracted)
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APASmart Define. (2015). loco thesaurus. Retrieved September 23, 2026, from https://smartdefine.org/loco/thesaurus/synonyms
ChicagoSmart Define. 2015. "loco thesaurus" https://smartdefine.org/loco/thesaurus/synonyms (accessed September 23, 2026).
HarvardSmart Define 2015, loco thesaurus, Smart Define, viewed 23 September, 2026, <https://smartdefine.org/loco/thesaurus/synonyms>.
MLASmart Define. "loco thesaurus" 10 April 2015. Web. 23 September 2026. <https://smartdefine.org/loco/thesaurus/synonyms>