43 entries under underhanded topic. ×

36
secret(adjective, quiet, show, dishonest, deceitful)
20
surreptitious(adjective, dishonest, deceitful, secret, hidden)
17
undercover(adjective, adverb, show, dishonest, secret)
17
concealed(adjective, obscure, secret, unknown, hidden)
15
stealthy(adjective, quiet, dishonest, secret, hidden)
14
hush-hush(adjective, adverb, show, informal, dishonest)
7
privy(adjective, special, intimate, secret, hidden)
6
veiled(adjective, secret, private, unknown, hidden)
5
deceitful(adjective, dishonest, sneaky, insincere)
4
shrouded(adjective, secret, unknown, hidden, concealed)
4
sneaking(adjective, dishonest, cunning, deceitful, secret)
3
oblique(dishonest, cunning, deceitful, sneaky)
2
buried(adjective, secret, unknown, hidden, concealed)
2
camouflaged(adjective, secret, hidden, underground, undisclosed)
2
deceptive(false, dishonest, cunning, deceitful, artful)
2
devious(dishonest, cunning, deceitful, sneaky)
2
incognito(secret, hidden, spy, underground, undisclosed)
2
shifty(dishonest, cunning, deceitful, sneaky)
2
under-the-table(secret, private, hidden, underground, sneaky)
1
cloaked(secret, unknown, hidden, concealed)
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APASmart Define. (2015). clandestine thesaurus. Retrieved September 24, 2026, from https://smartdefine.org/clandestine/thesaurus/synonyms
ChicagoSmart Define. 2015. "clandestine thesaurus" https://smartdefine.org/clandestine/thesaurus/synonyms (accessed September 24, 2026).
HarvardSmart Define 2015, clandestine thesaurus, Smart Define, viewed 24 September, 2026, <https://smartdefine.org/clandestine/thesaurus/synonyms>.
MLASmart Define. "clandestine thesaurus" 13 April 2015. Web. 24 September 2026. <https://smartdefine.org/clandestine/thesaurus/synonyms>