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.

Blockading merchant ships violates the UN Convention on the Law of the Sea and is illegal, she noted.

From Barron's • Apr. 14, 2026

Iran’s armed forces said before the U.S. blockade began that such a move would constitute an illegal “act of piracy.”

From The Wall Street Journal • Apr. 14, 2026

Pushbacks - forcing migrants and asylum seekers back across borders without due process - are generally considered illegal under international law.

From BBC • Apr. 14, 2026

“Pathogen transmission is a consequence of general and diverse uses of wildlife by people. This includes illegal and legal trade.”

From Los Angeles Times • Apr. 13, 2026

Under this law, the federal government must help recapture fugitives; to hide or “harbor” a fugitive is illegal.

From "In the Shadow of Liberty" by Kenneth C. Davis

Vocabulary lists containing illegal

List 3

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