1
fast
1
fast and loose(expression, adjective, idiom, dishonest, immoral)
1
feline
1
finagling
1
fixed(adjective, dishonest, immoral, rotten, untrustworthy)
1
forbidden(adjective, unreasonable, improper, excessive, unwarranted)
1
forsworn(adjective, mean, bad, evil, base)
1
gone to the dogs(expression, adjective, idiom, dishonest, immoral)
1
hidden(secret, clandestine, underground, undisclosed, sneaky)
1
hidlings
1
hush-hush(dishonest, cunning, deceitful, hidden, clandestine)
1
ill-got
1
ill-gotten
1
illegal(adjective, corrupt, unreasonable, dishonest, immoral)
1
illicit
1
improper(adjective, corrupt, unreasonable, dishonest, deceitful)
1
in ambush(expression, clandestine, underground, undisclosed)
1
incognito(secret, hidden, clandestine, underground, undisclosed)
1
inconstant(adjective, dishonest, immoral, unpredictable, rotten)
1
inept(adjective, unreasonable, improper, unwarranted, unnecessary)
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APASmart Define. (2016). underhanded thesaurus. Retrieved September 22, 2026, from https://smartdefine.org/underhanded/thesaurus/synonyms
ChicagoSmart Define. 2016. "underhanded thesaurus" https://smartdefine.org/underhanded/thesaurus/synonyms (accessed September 22, 2026).
HarvardSmart Define 2016, underhanded thesaurus, Smart Define, viewed 22 September, 2026, <https://smartdefine.org/underhanded/thesaurus/synonyms>.
MLASmart Define. "underhanded thesaurus" 22 January 2016. Web. 22 September 2026. <https://smartdefine.org/underhanded/thesaurus/synonyms>