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.

West Ham also issued a statement, saying Sullivan had denied any "illegal conduct" and was leaving "in order to avoid disruption to the club while he addresses the matter privately".

From BBC • Jun. 9, 2026

What’s Next: Kalshi and Polymarket are thriving in states like Texas and California, where traditional sports betting remains illegal, and prediction markets will be the only legal game in town for local bettors.

From Barron's • Jun. 8, 2026

In written testimony, Glynn shared his experience hearing about young women performing illegal abortions when he was a freshman at the University of South Dakota in 1966.

From Salon • Jun. 8, 2026

Officials also pledged to investigate illegal foreign-exchange transactions by exporters and importers through lead-and-lag practices—such as accelerating import payments or excessively delaying export receipts—activities the government has vowed to crack down on.

From The Wall Street Journal • Jun. 8, 2026

“Anyway, he’s done bad things. He made magic use illegal, and he called for the extermination of dragons.”

From Anya and the Dragon by Sofiya Pasternack

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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