10
weighty(adjective, clear, sound, right, reasonable)
9
well-founded(adjective, good, sound, right, reasonable)
9
absolute(adjective, clear, correct, honest, true)
9
confirmed(adjective, sound, right, reasonable, rational)
8
well-grounded(adjective, good, sound, right, reasonable)
8
compelling(adjective, clear, direct, sound, right)
8
exact(adjective, good, open, correct, honest)
8
forceful(adjective, clear, strong, power, direct)
8
forcible(adjective, strength, violent, important, powerful)
8
irrefutable(adjective, clear, sound, right, reasonable)
8
justifiable(adjective, reasonable, sensible, proper, logical)
8
meaningful(adjective, clear, significant, apt, effective)
7
binding(adjective, characteristic, sound, right, reasonable)
7
competent(adjective, good, power, suitable, acceptable)
7
reliable(adjective, good, clear, open, right)
7
adequate(adjective, good, power, suitable, acceptable)
6
rational(adjective, sound, reasonable, sensible, proper)
6
attested(adjective, sound, right, reasonable, rational)
6
authorized(adjective, fair, proper, legitimate, lawful)
6
certain(adjective, correct, honest, true, straight)
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APASmart Define. (2016). valid thesaurus. Retrieved September 20, 2026, from https://smartdefine.org/valid/thesaurus/synonyms
ChicagoSmart Define. 2016. "valid thesaurus" https://smartdefine.org/valid/thesaurus/synonyms (accessed September 20, 2026).
HarvardSmart Define 2016, valid thesaurus, Smart Define, viewed 20 September, 2026, <https://smartdefine.org/valid/thesaurus/synonyms>.
MLASmart Define. "valid thesaurus" 31 March 2016. Web. 20 September 2026. <https://smartdefine.org/valid/thesaurus/synonyms>