3
nasty(adjective, hard, rough, rude, cruel)
3
nefarious(adjective, dishonest, immoral, rotten, untrustworthy)
3
rotten(adjective, hard, evil, rough, nasty)
3
scheming
3
sneaky(adjective, false, deceitful, lying, subtle)
3
subversive(adjective, untrue, untrustworthy, treacherous, unfaithful)
3
unctuous(adjective, false, deceitful, lying, untruthful)
3
underhanded(adjective, mean, base, false, dishonest)
2
Janus-faced
2
Punic
2
alienated(adjective, untrue, untrustworthy, treacherous, unfaithful)
2
ambidextrous(false, dishonest, deceitful, lying, double)
2
baleful(adjective, malevolent)
2
base(adjective, mean, dishonest, immoral, rotten)
2
capricious(adjective, false, dishonest, dubious, untrustworthy)
2
cheating(adjective, false, dishonest, deceitful, lying)
2
churlish(adjective, hard, rough, nasty, rude)
2
counterfeit
2
dangerous(adjective, hard, evil, rough, nasty)
2
despicable(adjective, hard, evil, rough, nasty)
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APASmart Define. (2016). perfidious thesaurus. Retrieved September 20, 2026, from https://smartdefine.org/perfidious/thesaurus/synonyms
ChicagoSmart Define. 2016. "perfidious thesaurus" https://smartdefine.org/perfidious/thesaurus/synonyms (accessed September 20, 2026).
HarvardSmart Define 2016, perfidious thesaurus, Smart Define, viewed 20 September, 2026, <https://smartdefine.org/perfidious/thesaurus/synonyms>.
MLASmart Define. "perfidious thesaurus" 4 March 2016. Web. 20 September 2026. <https://smartdefine.org/perfidious/thesaurus/synonyms>