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.

Authorities have listed 16 people suspected of illegal trading activity and violations of the Capital Markets Act, including Rainbow Robotics’ head and CFO.

From MarketWatch • Jun. 11, 2026

"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 repeatedly denied any wrongdoing and rejected the idea that he knew anything about Epstein's illegal activity.

From BBC • 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

Anthony had been accused of breaking a law that prohibited willful and knowing illegal voting; she argued that she didn’t break the law because she believed her ballot was legal.

From "Votes for Women!" by Winifred Conkling

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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