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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.

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

Sanchez has always denied any illegal funding of his party and rebuffed calls for polls before the next scheduled general election, due in 2027.

From Barron's • Apr. 7, 2026

The appeals court ruled that Keenan couldn’t use the gun as evidence because police had conducted an illegal search, forcing Keenan to dismiss the case.

From The Wall Street Journal • Apr. 7, 2026

At first they made money from illegal logging and plantations, later benefitting from a speculative property boom in the cities fuelled by Chinese investors.

From BBC • Apr. 6, 2026

I explained that what the State had done to him was illegal and that we could pursue a civil action against them, but he had no interest in that.

From "Just Mercy" by Bryan Stevenson