17 entries under illogical topic. ×

15
irrational(adjective, sound, obscure, rational, senseless)
12
unreasonable(adjective, correct, right, obscure)
9
unsound(adjective, obscure)
4
foolish(adjective, sound, obscure, wise)
2
improbable(adjective, obscure)
2
invalid(adjective, sound, reasonable, obscure)
2
unlikely(adjective, obscure)
1
implausible(adjective, obscure)
1
obscure
1
stupid(adjective, obscure)
1
unclear(adjective, obscure)
1
unintelligent(adjective, obscure)
1
unwise(adjective, obscure)
0
optional(adjective, obscure)
0
unrealistic(adjective, obscure)
0
unsuitable(adjective, obscure)
0
vague(adjective, obscure)
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APASmart Define. (2015). logical thesaurus. Retrieved September 26, 2026, from https://smartdefine.org/logical/thesaurus/antonyms
ChicagoSmart Define. 2015. "logical thesaurus" https://smartdefine.org/logical/thesaurus/antonyms (accessed September 26, 2026).
HarvardSmart Define 2015, logical thesaurus, Smart Define, viewed 26 September, 2026, <https://smartdefine.org/logical/thesaurus/antonyms>.
MLASmart Define. "logical thesaurus" 19 October 2015. Web. 26 September 2026. <https://smartdefine.org/logical/thesaurus/antonyms>