2
informed
2
justifiable(adjective, good, wrong, reasonable, fair)
2
legitimate(adjective, false, improper, unlawful)
2
lucid(adjective, obscure, sensible, dark, clearheaded)
2
plausible(adjective, reasonable, believable)
2
pragmatic(adjective, correct, right, sensible, idealistic)
2
solid
2
warranted(adjective, good, fair)
2
well-founded
2
well-grounded
1
inexpensive
1
judicious(adjective, careless, foolish, unsound)
1
acceptable
1
actual
1
admissible
1
balanced
1
certain
1
certified
1
clear
1
cogent
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APASmart Define. (2015). unreasonable thesaurus. Retrieved September 27, 2026, from https://smartdefine.org/unreasonable/thesaurus/antonyms
ChicagoSmart Define. 2015. "unreasonable thesaurus" https://smartdefine.org/unreasonable/thesaurus/antonyms (accessed September 27, 2026).
HarvardSmart Define 2015, unreasonable thesaurus, Smart Define, viewed 27 September, 2026, <https://smartdefine.org/unreasonable/thesaurus/antonyms>.
MLASmart Define. "unreasonable thesaurus" 10 April 2015. Web. 27 September 2026. <https://smartdefine.org/unreasonable/thesaurus/antonyms>