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Added 5 October 2026

illegal

/ɪˈliːɡəl/ adjective

In Latin: illicitus Wiktionary

adjective Definition from Wiktionary (CC BY-SA). Pronunciation from Wiktionary, via Kaikki.org. More about illegal at Wordnik → Where our words come from →

Contrary to, forbidden, or not authorized by law, especially criminal law.
This is illegal, you know!
Forbidden by established rules.
Moving a pawn backward is an illegal move in chess.
Totally fictitious, and often issued on behalf of a non-existent territory or country.

noun

An illegal act or technique.
Contraband, esp. illegal substances such as drugs.
Ellipsis of illegal immigrant.

Origin

Borrowed from French illégal, from Medieval Latin illegalis, from Latin legalis, by surface analysis, il- + legal. In senses relating to immigration, via clipping of illegal alien or illegal immigrant.

From Wiktionary, via Kaikki.org (CC BY-SA)

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