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Showing results for illegal. Search instead for illegal/3.
Definitions

illegal

[ih-lee-guhl] / ɪˈli gəl /
ADJECTIVE
against the law
Synonyms
STRONGEST
banned criminal illegitimate illicit irregular outlawed prohibited smuggled unauthorized unconstitutional unlawful unlicensed unwarranted wrongful
WEAK
actionable black-market bootleg contraband crooked extralegal felonious forbidden heavy hot interdicted lawless not approved not legal outside the law proscribed prosecutable racket shady sub-rosa taboo under-the-table unofficial unwarrantable verboten violating wildcat
Antonyms
STRONGEST
authorized blessed ethical good justifiable lawful legal legitimate moral permitted right warranted
WEAK
allowed permissible

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Oregon’s Worker Fraud Protection Act makes it illegal to “falsely impersonate” a union representative and imposes fines for infractions.

From The Wall Street Journal • Apr. 1, 2026

Every lower court that has considered the issue has found the order illegal and prevented it from taking effect.

From Los Angeles Times • Apr. 1, 2026

In France - one of a number of countries where genetic testing is illegal without a medical prescription due to privacy laws - the government has condemned the decision as "a step backwards".

From BBC • Mar. 31, 2026

That’s illegal, and we’re going to get the courts to say so.

From Slate • Mar. 30, 2026

People of all races use and sell illegal drugs at remarkably similar rates.

From "The New Jim Crow" by Michelle Alexander

From Roget's 21st Century Thesaurus, Third Edition Copyright © 2013 by the Philip Lief Group.