Illicit \Il*lic"it\, a. [L. illicitus; pref. il- not + licitus, p. p. of licere to be allowed or permitted: cf. F. illicite. See In- not, and License.]

Not permitted or allowed; prohibited; unlawful; as, illicit trade; illicit intercourse; illicit pleasure.

One illicit . . . transaction always leads to another. --Burke. -- Il*lic"it*ly, adv. -- Il*lic"it*ness, n.

Source: Webster's Revised Unabridged Dictionary (1913)