9
ascertain(verb, state, confirm, verify, ascertain)
8
assert(verb, support, maintain, back, confirm)
8
aver(verb, support, state, maintain, secure)
8
check(verb, ascertain)
8
hearten(verb, encourage, raise, cheer, speech)
8
inspire(verb, encourage, cheer, speech, comfort)
8
make certain(verb, expression, idiom, support, maintain)
8
tell
8
vouch(verb, support, state, give, back)
8
warranty
7
prove(verb, support, get, maintain, secure)
7
determine(verb, settle, decide, certainty, seal)
7
establish(verb, get, secure, settle, influence)
7
settle(verb, calm, relax, strengthen, relieve)
7
vouch for(verb, expression, phrasal verb, support, maintain)
6
avouch(verb, affirm, affirmation)
6
clinch(verb, secure, settle, establish, confirm)
6
comfort(verb, encourage, cheer, inspire, promise)
6
induce(verb, get, meet, encourage, do)
6
safeguard(verb, support, cover, keep, maintain)
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APASmart Define. (2015). assure thesaurus. Retrieved September 23, 2026, from https://smartdefine.org/assure/thesaurus/synonyms
ChicagoSmart Define. 2015. "assure thesaurus" https://smartdefine.org/assure/thesaurus/synonyms (accessed September 23, 2026).
HarvardSmart Define 2015, assure thesaurus, Smart Define, viewed 23 September, 2026, <https://smartdefine.org/assure/thesaurus/synonyms>.
MLASmart Define. "assure thesaurus" 10 April 2015. Web. 23 September 2026. <https://smartdefine.org/assure/thesaurus/synonyms>