illicitly

Illicitly is an adverb describing the manner in which an action is performed when that action is not permitted by law, regulation, or established rules, or when it violates commonly accepted moral norms. It is typically used to characterize how something is done rather than the act itself, and it often applies to activities that are illegal, regulated, or socially disapproved.

Etymology and form. The adverb is derived from the adjective illicit, which comes from Old French illicite and from Latin illicitus meaning “not permitted,” formed with the negative prefix in- added to licere “to be permitted.” The suffix -ly turns the adjective into the adverb illicitly.

Usage and nuance. Illicitly tends to appear in formal or analytical writing, including legal, journalistic, and academic contexts. It can imply a normative judgment beyond strict legality, suggesting disapproval or concealment. Its meaning overlaps with legally illegal, but the term often emphasizes the prohibited or hidden nature of the conduct rather than a purely technical violation of statute. In everyday language, illegally is more common when the focus is squarely on breaking the law, while illicitly highlights the illicit character of the act itself.

Related terms. Illicit is the related adjective; illegality and illegitimate cover broader notions of unlawfulness or inappropriateness, whereas illicitly specifically denotes the manner of performing an illicit act. See also topics related to illicit trade, illicit drugs, and other forms of prohibited activity.