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.

In Brazil, it’s illegal to possess a wild animal without authorization from the government.

From Slate • May 27, 2026

It will involve France deploying millions of pounds worth of drones, two helicopters and a camera system to intercept people smugglers and illegal migrants.

From BBC • May 26, 2026

Authorities say the cause of the disaster is still under investigation, but initial findings show Tongzhou Group, the company operating the privately-owned coal mine had committed "serious illegal violations".

From BBC • May 25, 2026

South African government ministers held urgent talks Monday to address tensions over illegal migration as protesters again demanded that undocumented foreign nationals be made to leave the country.

From Barron's • May 25, 2026

“I’m an upstanding businessman. I would never be involved in illegal enterprises.”

From Full of Beans by Jennifer L. Holm

Vocabulary lists containing illegal

List 3

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