DictionaryillegalAgainst the law or rules
adjective / noun

illegal

ih-LEE-guhl/ɪˈliːɡl/

Contrary to the requirements of law.

A park ranger stops an illegal entry into a protected area.

A person attempts to enter a fenced protected area through a cut fence while a park ranger stops the intruder, small indispensable prohibition pictogram only, no words.
Etymology

Latin legalis described what pertained to law. With the negative prefix, illegal means contrary to law, not simply unrelated to legal matters.

In context

ORCA Media30:14
that's illegal we're not part we're not allowed to be partisan houses of worship aren't either although some of them do it
Spotlight on Vermont Issues: Religious Freedom

More examples

  • Selling alcohol to minors is illegal.
  • The referee penalizes the team for an illegal substitution.
  • Calling undocumented immigrants "illegals" is often considered offensive.

Forms

illegal · illegals

illegally adverb — In a way that violates the law.

illegality noun — The state of being against the law.

Similar words

unlawful
Directly describes a violation of law, not merely official rules.
illicit
Often suggests secret or socially disapproved activity, not necessarily lawbreaking.
prohibited
Means expressly forbidden, whether by law, policy, or individual authority.