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English definition of “illegal”


LAW not allowed by law: According to state law, smoking is illegal in all public buildings.illegal (for sb) to do sth It is illegal for a company to force an employee into early retirement.make sth illegal The new law will make it illegal to record phone conversations without consent. illegal sales/profits/trades → Compare legal
IT used to describe a character (= letter, number, or symbol) that you cannot use in a particular place on a computer, because it may create problems: The colon is the only illegal character for file and folder names.
illegally adverb
(Definition of illegal from the Cambridge Business English Dictionary © Cambridge University Press)
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