75
certain(adjective, good, set, clear, understanding)
41
positive(adjective, good, set, clear, strong)
35
definite(adjective, good, clear, strong, complete)
33
confident(adjective, calm, clear, strong, easy)
28
indisputable(adjective, clear, certain, true, definite)
26
unquestionable(adjective, flat, total, solid, perfect)
24
secure(verb, adjective, calm, quality, strong)
23
assured(verb, adjective, clear, understanding, strong)
23
undeniable(adjective, clear, firm, perfect, certain)
23
incontestable(adjective, certain, true, definite, ideal)
22
firm(noun, adjective, calm, good, close)
22
reliable(adjective, calm, close, clear, strong)
21
incontrovertible(adjective, certain, true, definite, ideal)
20
unequivocal(adjective, good, clear, strong, flat)
19
absolute(adjective, clear, strong, sound, complete)
19
solid(adjective, calm, good, quality, strong)
18
safe(adjective, calm, good, quality, clear)
18
steady(adjective, calm, good, close, quality)
17
indubitable(adjective, set, clear, sound, correct)
17
irrefutable(adjective, clear, firm, solid, certain)
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APASmart Define. (2016). sure thesaurus. Retrieved September 20, 2026, from https://smartdefine.org/sure/thesaurus/synonyms
ChicagoSmart Define. 2016. "sure thesaurus" https://smartdefine.org/sure/thesaurus/synonyms (accessed September 20, 2026).
HarvardSmart Define 2016, sure thesaurus, Smart Define, viewed 20 September, 2026, <https://smartdefine.org/sure/thesaurus/synonyms>.
MLASmart Define. "sure thesaurus" 31 March 2016. Web. 20 September 2026. <https://smartdefine.org/sure/thesaurus/synonyms>