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.

Sir Martyn Oliver told the BBC's Today programme that the practice of companies themselves running illegal placements was a "scandal" and that they will face fines.

From BBC • Jul. 8, 2026

Multiple parties concluded that the wall was illegal.

From The Wall Street Journal • Jul. 8, 2026

Clark Birdsall was not the attorney on those cases but defended another resident whom Paxton prosecuted for illegal voting.

From Salon • Jul. 7, 2026

And just a few weeks ago, civil rights lawyers joined with parents’ and children’s advocates to bring landmark class-action litigation to end illegal family separations.

From Slate • Jul. 7, 2026

I hadn't told the officers I was a lawyer or informed them that what they were doing was illegal.

From "Just Mercy" by Bryan Stevenson

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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