Synonyms|1.1kAntonyms|412|Broader|17Narrower|24Related|3.7k
3
irrefutable
3
likely
3
plausible
3
positive(adjective, certain, definite)
3
possible
3
probable
3
resolute
3
sanguine
3
trusting
3
unarguable
3
undeniable
2
determined
2
most likely
2
believable
2
decisive
2
accomplished
2
conceivable
2
confirmed(verb, adjective)
2
decided
2
dependable
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APASmart Define. (2016). doubtful thesaurus. Retrieved September 24, 2026, from https://smartdefine.org/doubtful/thesaurus/antonyms
ChicagoSmart Define. 2016. "doubtful thesaurus" https://smartdefine.org/doubtful/thesaurus/antonyms (accessed September 24, 2026).
HarvardSmart Define 2016, doubtful thesaurus, Smart Define, viewed 24 September, 2026, <https://smartdefine.org/doubtful/thesaurus/antonyms>.
MLASmart Define. "doubtful thesaurus" 24 March 2016. Web. 24 September 2026. <https://smartdefine.org/doubtful/thesaurus/antonyms>