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.

Illegal listings were scattered across the Southland, but the report said that 42% were found in L.A.

From Los Angeles Times • Feb. 11, 2026

Illegal cattle ranching has already destroyed millions of acres.

From Science Daily • Nov. 22, 2025

Reacting to our investigation, Home Secretary Shabana Mahmood, said: "Illegal working and linked organised criminality creates an incentive for people to come here illegally. We will not stand for it."

From BBC • Nov. 4, 2025

Illegal border crossings have slowed to a near-halt, and the labor-participation rate among foreign-born workers continues to fall.

From Barron's • Oct. 9, 2025

Illegal to keep them in Maryland—you know, an effort to help boost the crab population.

From "Red Kayak" by Priscilla Cummings

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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