9
sincere(adjective, open, honest, false, straightforward)
7
honest(adjective, open, false, corrupt, sincere)
5
naive
4
earnest(adjective, cool, cold, important)
4
realistic(adjective, genuine, unsound)
3
frank(adjective, open, honest, dishonest, sincere)
3
unfeigned(adjective, sincere)
3
wholehearted(adjective, sincere)
3
wow
2
devout(adjective, cool, devoted, believing)
2
genuine(adjective, open, honest, uncertain, sincere)
2
heartfelt(adjective, cool, cold, genuine)
2
open(adjective, sincere)
2
forthright(adjective, open, sincere)
2
straightforward(adjective, open, dishonest, sincere)
2
true(wrong, improper, incorrect)
1
artless
1
candid
1
cordial(cool, rude, unfriendly)
1
direct(adjective, open, sincere)
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APASmart Define. (2016). insincere thesaurus. Retrieved September 29, 2026, from https://smartdefine.org/insincere/thesaurus/antonyms
ChicagoSmart Define. 2016. "insincere thesaurus" https://smartdefine.org/insincere/thesaurus/antonyms (accessed September 29, 2026).
HarvardSmart Define 2016, insincere thesaurus, Smart Define, viewed 29 September, 2026, <https://smartdefine.org/insincere/thesaurus/antonyms>.
MLASmart Define. "insincere thesaurus" 14 March 2016. Web. 29 September 2026. <https://smartdefine.org/insincere/thesaurus/antonyms>