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.

But the U.S. can’t stop the illegal flow of oil solely by chasing tankers at sea.

From The Wall Street Journal • May 28, 2026

Courts can block abuses of federal power, including illegal arrests, detentions and mass citizen databases.

From Salon • May 28, 2026

The European Commission said Temu failed to properly assess the platform's design and how it "could amplify dissemination risks of illegal products".

From Barron's • May 28, 2026

Some of the rubbish dates back as far as the 1960s but the illegal waste was linked to two businessmen who were jailed for their role in the scandal in June last year.

From BBC • May 27, 2026

My father found his own way to defy the Nazis and to help us survive at the same time, even though it meant doing something illegal.

From "The Boy on the Wooden Box" by Leon Leyson

Vocabulary lists containing illegal

List 3

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