illegal

1 of 2

adjective

il·​le·​gal (ˌ)i(l)-ˈlē-gəl How to pronounce illegal (audio)
Synonyms of illegal
: not according to or authorized by law : contrary to or in violation of a law : unlawful, illicit
also : not sanctioned by official rules (as of a game)
illegality
ˌi-li-ˈga-lə-tē How to pronounce illegal (audio)
noun
illegally
(ˌ)i(l)-ˈlē-gə-lē How to pronounce illegal (audio)
adverb

illegal

2 of 2

noun

plural illegals
often disparaging + offensive
: a person who enters or lives in a country without the documentation required for legal entry or residence

Synonyms of illegal

Relevance

Adjective

See All Synonyms & Antonyms in Thesaurus

Examples of illegal in a Sentence

Adjective In this state, it is illegal for anyone under the age of 21 to drink alcohol. The team was penalized for an illegal play.

Word History

Etymology

Adjective

Middle French or Medieval Latin; Middle French illegal, from Medieval Latin illegalis, from Latin in- + legalis legal

First Known Use

Adjective

1624, in the meaning defined above

Noun

1939, in the meaning defined above

Time Traveler
The first known use of illegal was in 1624

Rhymes for illegal

See All Rhymes for illegal

Browse Nearby Words

Illecebraceae
illegal
illegal immigrant
See all Nearby Words

Cite this Entry

“Illegal.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/illegal. Accessed 6 Jul. 2026.

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Kids Definition

illegal

adjective
il·​le·​gal
(ˈ)il-ˈ(l)ē-gəl
: contrary to the laws or rules : unlawful
illegality
ˌil-i-ˈgal-ət-ē
noun
illegally
(ˈ)il-ˈ(l)ē-gə-lē
adverb

Legal Definition

illegal

adjective
il·​le·​gal il-ˈlē-gəl How to pronounce illegal (audio)
: contrary to or in violation of a law : illicit, unlawful
an illegal contract
illegally adverb

More from Merriam-Webster on illegal

Nglish: Translation of illegal for Spanish Speakers

Last Updated: - Definition revised
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