15 entries under idiom topic. ×

5
against the law(expression, adjective, wrong, illegal)
4
contrary to law(expression, adjective, legal, illegal)
2
out of bounds(expression, adjective)
1
in violation of law(expression, adjective, legal, illegal)
1
out of line(expression, adjective, wrong, senseless)
1
under the ban
0
against principle
0
cloak and dagger(expression, hidden, fraudulent)
0
forbidden by law
0
if indeed
0
if only
0
illegal trade
0
in holes and corners(expression, hidden, sly, fraudulent)
0
not allowed(expression, illegality)
0
on the quiet(expression, hidden, sly, fraudulent)
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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>