16
unfailing(adjective, certain, true, definite, reliable)
16
clear(adjective, complete, flat, firm, total)
16
trustworthy(adjective, good, close, clear, strong)
15
convinced(verb, adjective, clear, belief, certain)
15
infallible(adjective, clear, complete, property, certain)
14
dependable(adjective, good, close, strong, correct)
14
inevitable(adjective, certain, obvious, expected, predictable)
14
stable(adjective, good, quality, strong, easy)
14
steadfast(adjective, calm, good, close, strong)
14
unavoidable(adjective, certain, obvious, bound, necessary)
14
undisputed(adjective, ideal, accepted, all time, the best)
13
decided(adjective, clear, solid, perfect, certain)
13
determined(verb, adjective, good, clear, strong)
13
fixed(adjective, clear, strong, flat, firm)
13
strong(adjective, calm, good, strong, tough)
13
trusty(adjective, good, close, strong, correct)
13
unmistakable(adjective, clear, plain, energetic, certain)
11
certainly(adjective, adverb, interjection, fine, certainty)
11
categorical(adjective, clear, complete, flat, total)
11
destined(adjective, clear, obvious, valid, necessary)
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APASmart Define. (2016). sure thesaurus. Retrieved September 21, 2026, from https://smartdefine.org/sure/thesaurus/synonyms
ChicagoSmart Define. 2016. "sure thesaurus" https://smartdefine.org/sure/thesaurus/synonyms (accessed September 21, 2026).
HarvardSmart Define 2016, sure thesaurus, Smart Define, viewed 21 September, 2026, <https://smartdefine.org/sure/thesaurus/synonyms>.
MLASmart Define. "sure thesaurus" 31 March 2016. Web. 21 September 2026. <https://smartdefine.org/sure/thesaurus/synonyms>