Prostitution is illegal in some countries.
- It is illegal to do a U-turn on a motorway.
- The proposed change in the law would make abortion illegal except for strictly defined medical reasons.
- It's illegal to discriminate against people on the basis of their sex.
- For a teacher to hit a child is not just morally wrong but also illegal.
- Several athletes tested positive for illegal performance-enhancing drugs.
illegalnoun [ C ]informal
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