80 entries under fair topic. ×

53
reasonable(adjective, calm, good, quiet, hard)
44
sensible(adjective, calm, good, clear, understanding)
38
sound(noun, adjective, calm, good, quiet)
35
intelligent(adjective, clear, sound, reasonable, moderate)
32
logical(adjective, good, clear, sound, reasonable)
32
judicious(adjective, calm, good, clear, understanding)
31
wise(adjective, calm, good, clear, understanding)
20
lucid(adjective, calm, quiet, clear, sound)
14
discriminating(adjective, clear, sound, reasonable, sensible)
12
commonsensical(adjective, calm, good, clear, sound)
10
plausible(adjective, clear, sound, reasonable, sensible)
10
ratiocinative(adjective, clear, sound, reasonable, reason)
10
discreet(adjective, calm, understanding, reasonable, keen)
9
acceptable(adjective, sound, reasonable, honest, solid)
8
analytical(adjective, clear, sound, reasonable, reason)
8
consequent(adjective, good, clear, sound, reasonable)
8
credible(adjective, sound, reasonable, sensible, solid)
8
discerning(adjective, clear, understanding, sound, reasonable)
8
justifiable(adjective, clear, sound, reasonable, honest)
7
coherent(adjective, clear, sound, reasonable, sensible)
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APASmart Define. (2016). rational thesaurus. Retrieved September 22, 2026, from https://smartdefine.org/rational/thesaurus/synonyms
ChicagoSmart Define. 2016. "rational thesaurus" https://smartdefine.org/rational/thesaurus/synonyms (accessed September 22, 2026).
HarvardSmart Define 2016, rational thesaurus, Smart Define, viewed 22 September, 2026, <https://smartdefine.org/rational/thesaurus/synonyms>.
MLASmart Define. "rational thesaurus" 29 March 2016. Web. 22 September 2026. <https://smartdefine.org/rational/thesaurus/synonyms>