11
doubtless(adjective, adverb, certain, definite, certainty)
11
fast(adjective, calm, close, quality, strong)
11
set(verb, adjective, calm, strong, secure)
11
surely(adverb, absolutely, really, positively, easily)
11
undoubted(adjective, clear, sound, correct, firm)
11
unerring(adjective, clear, complete, property, certain)
11
unfaltering(adjective, complete, firm, total, solid)
11
unqualified(adjective, clear, strong, complete, flat)
10
accurate(adjective, close, set, clear, correct)
10
cocksure(adjective, clear, belief, certain, behaviour)
10
decisive(adjective, good, clear, strong, honest)
10
inarguable(adjective, certain, true, ideal, all time)
10
true(adjective, adverb, good, close, clear)
10
unwavering(adjective, calm, close, strong, secure)
9
explicit(adjective, clear, strong, complete, flat)
9
faithful(adjective, good, close, strong, correct)
9
fated(adjective, definite, absolute, obvious, necessary)
9
guaranteed(adjective, clear, hard, sound, firm)
9
irrefragable(adjective, certain, ideal, all time, the best)
9
satisfied(verb, adjective, belief, certain, definite)
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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>