2
mentally strange(expression, silly, foolish, mad, insane)
2
neurotic
2
nutty as fruitcake(expression, idiom, silly, foolish, mad)
2
off-the-wall
2
off one's chump
2
off one's rocker
2
personal quality(adjective, feature, characteristic, attribute, own)
2
philosophic(adjective, reasoning, intellectual)
2
psychoanalytical(adjective, psychical)
2
psychoneurotic
2
psychopath
2
queer
2
quirky
2
reasonless
2
reflecting
2
round the bend(expression, idiom, silly, foolish, mad)
2
ruminant
2
ruminating
2
screw loose(expression, silly, foolish, mad, insane)
2
serious
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APASmart Define. (2015). mental thesaurus. Retrieved September 22, 2026, from https://smartdefine.org/mental/thesaurus/synonyms
ChicagoSmart Define. 2015. "mental thesaurus" https://smartdefine.org/mental/thesaurus/synonyms (accessed September 22, 2026).
HarvardSmart Define 2015, mental thesaurus, Smart Define, viewed 22 September, 2026, <https://smartdefine.org/mental/thesaurus/synonyms>.
MLASmart Define. "mental thesaurus" 10 April 2015. Web. 22 September 2026. <https://smartdefine.org/mental/thesaurus/synonyms>