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Showing results for illegal. Search instead for prelegal.
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 1966, he led the workers on an illegal strike, paralyzing the city and its idealistic new mayor, John V. Lindsay.

From The Wall Street Journal • Apr. 10, 2026

After Thursday's raids, which started in the morning were still ongoing well into the night, the police detained one of the paper's top investigative reporters on alleged illegal personal data use, Novaya Gazeta said.

From Barron's • Apr. 9, 2026

Kalshi CEO Tarek Mansour called the ruling a win, as various states have filed lawsuits against Kalshi, arguing its operations constitute illegal gambling.

From The Wall Street Journal • Apr. 7, 2026

The US State Department said that while it did not comment on "diplomatic communications with other governments" the government remained "unwavering" in its "commitment to end illegal and mass immigration and bolster America's border security".

From BBC • Apr. 6, 2026

She told a Treasury official that she wanted to lobby for a law making it illegal to mention government workers by name without their permission.

From "The Woman All Spies Fear" by Amy Butler Greenfield