illicit has definitions from the fields of law,sexuality
1
[ adjective ] (sexuality) contrary to accepted morality (especially sexual morality) or convention

Examples

"an illicit association with his secretary"

Used in print

(Guy Bolton, The Olympians....)

The place was evidently a familiar haunt and Claire wondered what other illicit loves had been celebrated in the comfortable rooms to which they were shown .

Related terms

licit adulterous unlawful

2
[ adjective ] (law) contrary to or forbidden by law

Examples

"an illegitimate seizure of power" "illicit trade" "an outlaw strike" "unlawful measures"

Related terms

illegal

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