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.

You can use the adjective illegal to describe breaking the rules, as when you head-butt someone in a game. Acts that go against the law, such as robbing a bank, are also illegal. There is a wide range of things called illegal, from small acts to big ones, but no matter the seriousness, if it is against the law, it is illegal. This adjective also describes people who enter countries without official government approval, they are called "illegal immigrants" or "illegal aliens."

Definitions of illegal
  1. adjective
    prohibited by law or by official or accepted rules
    “an illegal chess move”
    contrary to or prohibited by or defiant of law
    of a crime or misdemeanor; punishable by a fine set by a judge
    banned, prohibited
    forbidden by law
    black, black-market, bootleg, contraband, smuggled
    distributed or sold illicitly
    criminal, felonious
    involving or being or having the nature of a crime
    dirty, ill-gotten
    obtained illegally or by improper means
    embezzled, misappropriated
    taken for your own use in violation of a trust
    beyond the usual course of legal proceedings; legally unwarranted
    extralegal, nonlegal
    not regulated or sanctioned by law
    recently stolen or smuggled
    illegitimate, illicit, outlaw, outlawed, unlawful
    contrary to or forbidden by law
    prohibited by official rules
    misbranded, mislabeled
    branded or labeled falsely and in violation of statutory requirements
    penal, punishable
    subject to punishment by law
    done or sold illicitly and secretly;
    lacking legal authority
    of marriages and offspring; not recognized as lawful
    contrary to rule or accepted order or general practice
    see moresee less
    established by or founded upon law or official or accepted rules
    conformable to or allowed by law
    ordered by a court of law
    decreed by or proceeding from a court of justice
    jural, juristic
    of or relating to law or to legal rights and obligations
    lawful, legitimate, licit
    authorized, sanctioned by, or in accordance with law
    ratified, sanctioned
    formally approved and invested with legal authority
    prescribed or authorized by or punishable under a statute
    sub judice
    before a judge or court of law; awaiting judicial determination
    of marriages and offspring; recognized as lawful
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DISCLAIMER: These example sentences appear in various news sources and books to reflect the usage of the word ‘illegal'. Views expressed in the examples do not represent the opinion of or its editors. Send us feedback
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