The meaning of ILLEGAL is not according to or authorized by law : contrary to or in violation of a law : unlawful, illicit; also : not sanctioned by official rules (as of a game). How to use illegal in …

ILLEGAL definition: forbidden by law or statute. See examples of illegal used in a sentence.

ILLEGAL definition: 1. not allowed by law: 2. not allowed by the rules of a sport: 3. an offensive word for someone…. Learn more.

1. Prohibited by law. 2. Prohibited by official rules: an illegal pass in football. 3. Unacceptable to or not performable by a computer: an illegal operation.

Dec 11, 2025 · According to Black's Law Dictionary (2nd edition), "illegal" may mean only that something lacks authority of the law or support from law (that is, that it's not legal), not that it's …

If something is illegal, the law says that it is not allowed. It is illegal to intercept radio messages. ...illegal drugs.

Something illegal is against the law or breaks the rules. If you're reading this in jail, you've probably done something illegal, and if you're not in jail, there's plenty of time to obey the law.

Definition of illegal adjective in Oxford Advanced Learner's Dictionary. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more.

Find 66 different ways to say ILLEGAL, along with antonyms, related words, and example sentences at Thesaurus.com.

Illegal is the most common of these three words, so unless you have a very specific circumstance, it will work in most cases. Also, it’s important to note that illegal is not the same thing as …