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.

"Before 2022, there were many ways to avoid the draft without doing anything illegal," said Artyom Klyga, a lawyer with the Movement of Conscientious Objectors.

From Barron's • Jun. 11, 2026

He has denied any wrongdoing and knowing about Epstein's illegal activity.

From BBC • Jun. 10, 2026

Prediction-market platform Kalshi recently unveiled a swath of “market integrity” updates that all relate to one thing: stopping illegal trading by insiders.

From MarketWatch • Jun. 10, 2026

Jordan’s control of the area was overwhelmingly considered an illegal occupation by the international community.

From The Wall Street Journal • Jun. 10, 2026

By 1787, when the Constitution was being drafted, most of the Northern states had already made the foreign slave trade illegal.

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

Vocabulary lists containing illegal

List 3

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"A Natural Balance" and "In My Dreams"

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Fear and Loathing in Cleveland: Trump's RNC Acceptance Speech

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