12 entries under sly topic. ×

6
clandestine(adjective, secret, legal, forbidden)
3
sneaky(adjective, fraudulent)
2
under-the-counter(hidden, illegal, fraudulent, illegitimate)
1
fraudulent(adjective, hidden)
0
artful(hidden, fraudulent)
0
cloak-and-dagger(hidden, fraudulent)
0
closet(hidden, fraudulent)
0
foxy(hidden, fraudulent)
0
in holes and corners(expression, idiom, hidden, fraudulent)
0
on the quiet(expression, idiom, hidden, fraudulent)
0
under cover(expression, fraudulent)
0
undercover
11 years ago|8.6k views|share |citing 
APASmart Define. (2015). illicit thesaurus. Retrieved September 24, 2026, from https://smartdefine.org/illicit/thesaurus/synonyms
ChicagoSmart Define. 2015. "illicit thesaurus" https://smartdefine.org/illicit/thesaurus/synonyms (accessed September 24, 2026).
HarvardSmart Define 2015, illicit thesaurus, Smart Define, viewed 24 September, 2026, <https://smartdefine.org/illicit/thesaurus/synonyms>.
MLASmart Define. "illicit thesaurus" 13 April 2015. Web. 24 September 2026. <https://smartdefine.org/illicit/thesaurus/synonyms>