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.

The statement continued: “ICE conducted a routine vehicle stop on a car registered to an illegal alien. After Venegas’ identity was established, he was released.”

From Salon • May 24, 2026

Italy's "Land of Fires", also known as the "Triangle of Death", has served as a dump and illegal incineration site since the late 1980s.

From Barron's • May 23, 2026

In its online advice, the RAC added: "Misuse of a car horn is illegal and can result in fines for the driver and owner of the vehicle."

From BBC • May 23, 2026

China's government launched an "uncompromising" investigation into the explosion, vowing to severely punish those responsible, and ordered a nationwide crackdown on illegal mining activities, Xinhua said Saturday evening.

From Barron's • May 23, 2026

She thought for certain it would have been illegal to say out loud.

From "A Place to Belong" by Cynthia Kadohata

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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