adjective
illegal
ih-LEE-guhl
adjective
1
Against the law; not authorised or permitted by legislation.
"It is illegal to drive without a valid licence."
"The factory was fined for illegal dumping of waste."
How to Use Illegal
Learner’s notesIn plain EnglishNot permitted by the law — the opposite of legal.
Common mistake
Don't confuse with "illicit," which can describe things that are socially disapproved of even if not technically criminal.
Easily confused with
Common pairings
illegal activity
illegal immigrant
declare illegal
Word Forms
more illegal comparative, illegaler comparative, illegals plural, most illegal superlative, illegalest superlative
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It is _____ to drive without a valid licence.
Etymology
Borrowed from French illégal, from Medieval Latin illegalis — "not" (il-) + "legal" (legalis).