107 entries under irrational topic. ×

6
far-fetched(adjective, hard, great, extraordinary, strange)
6
inconsistent(adjective, foolish, stupid, senseless, absurd)
6
lunatic(adjective, weak, simple, knowledge, ability)
6
screwy(adjective, great, wrong, extraordinary, wild)
5
erratic(adjective, wrong, wild, strange, silly)
4
impracticable(adjective, wild, strange, silly, foolish)
4
nuts(adjective, wild, silly, foolish, stupid)
3
fallacious(adjective, foolish, unreasonable, absurd)
3
foolhardy(adjective, simple, wild, strange, silly)
3
imprudent(adjective, weak, simple, wrong, severe)
3
invalid(adjective, foolish, unreasonable, absurd)
3
reckless(adjective, careless, wild, silly, foolish)
3
unrestrained(adjective, rough, foolish, crazy, unreasonable)
2
contradictory(adjective, foolish, stupid, senseless, absurd)
2
false(wrong, awkward, irregular, unsuitable)
2
flighty(adjective, simple, careless, wild, foolish)
2
giddy(adjective, simple, rough, careless, wild)
2
rash(adjective, careless, wild, silly, foolish)
2
raving(adjective, wrong, wild, silly, foolish)
2
reasonless(foolish, stupid, unreasonable, senseless)
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APASmart Define. (2015). preposterous thesaurus. Retrieved September 23, 2026, from https://smartdefine.org/preposterous/thesaurus/synonyms
ChicagoSmart Define. 2015. "preposterous thesaurus" https://smartdefine.org/preposterous/thesaurus/synonyms (accessed September 23, 2026).
HarvardSmart Define 2015, preposterous thesaurus, Smart Define, viewed 23 September, 2026, <https://smartdefine.org/preposterous/thesaurus/synonyms>.
MLASmart Define. "preposterous thesaurus" 2 September 2015. Web. 23 September 2026. <https://smartdefine.org/preposterous/thesaurus/synonyms>