il·​le·​gal | \ (ˌ)i(l)-ˈlē-gəl How to pronounce illegal (audio) \

Definition of illegal

 (Entry 1 of 2)

: not according to or authorized by law : unlawful, illicit also : not sanctioned by official rules (as of a game)



Definition of illegal (Entry 2 of 2)

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

Other Words from illegal


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

Synonyms & Antonyms for illegal

Synonyms: Adjective

Antonyms: Adjective

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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.
Recent Examples on the Web: Adjective Louisville police say anything that goes into the air or explodes is illegal for average citizens. James Bruggers, The Courier-Journal, 5 July 2017 Official fireworks shows took place over the city, and illegal pyrotechnics lit up the sky everywhere in between. Lisa Beebe, Los Angeles Magazine, 5 July 2017 Facebook has been scrutinized for its handling of its users’ data, and social networks face fines in Germany for failing to swiftly take down hate speech and illegal content. Amie Tsang, New York Times, 4 July 2017 In the 1950s and 1960s, major city hospitals in the United States admitted as many as 20 to 30 women a day for complications from illegal or self-induced abortions. Cindy Crabb, Teen Vogue, 1 July 2017 Will Ferrell and Amy Poehler as a stuck-in-a-rut suburban couple who open an illegal casino to pay for their daughter's college tuition. Owen Gleiberman,, 30 June 2017 They are charged with illegal re-entry into the United States after previous deportation or removal, according to Acting U.S. Attorney Robert O. Posey and U.S. Immigrations and Customs Enforcement Special Agent in Charge Ray Parmer. Carol Robinson,, 30 June 2017 Trump later walked back these comments, sort of, saying that instead, doctors should be punished for providing abortions if the procedure were made illegal. Michael Sebastian, Cosmopolitan, 29 June 2017 A Helsinki district court on Wednesday ordered the assets of Uber's Finnish country manager be confiscated until police conclude an investigation into whether the U.S. ride-hailing firm operates an illegal taxi service in Finland. Reuters, Fortune, 28 June 2017 Recent Examples on the Web: Noun And beyond stripping illegals of Austrian citizenship, Interior Minister Wolfgang Sobotka of the centrist People’s Party is proposing hefty fines and other punitive measures. George Jahn, The Seattle Times, 24 June 2017 Still, undercover illegals have been discovered in the United States as recently as June 2010, when 10 alleged spies were arrested by the FBI in Boston, New York, New Jersey and Arlington, Va. Harrison Smith, Washington Post, 21 June 2017 Marco stood today, standing on this stage Marco supports legalization and citizenship for 12 million illegals. New York Times, 15 Jan. 2016 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'illegal.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of illegal


1538, in the meaning defined above


1939, in the meaning defined above

History and Etymology for illegal


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

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Time Traveler for illegal

Time Traveler

The first known use of illegal was in 1538

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Dictionary Entries Near illegal

ill effect


illegal alien

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Statistics for illegal

Cite this Entry

“Illegal.” Dictionary, Merriam-Webster, Accessed 4 Oct. 2022.

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More Definitions for illegal


il·​le·​gal | \ i-ˈlē-gəl How to pronounce illegal (audio) \

Kids Definition of illegal

: not allowed by the laws or rules He was arrested for illegal activities. The team made an illegal play.

Other Words from illegal

illegally \ i-​ˈlē-​gə-​lē \ adverb


il·​le·​gal | \ il-ˈlē-gəl How to pronounce illegal (audio) \

Legal Definition of illegal

: contrary to or in violation of a law : illicit, unlawful an illegal contract

Other Words from illegal

illegally adverb

More from Merriam-Webster on illegal

Nglish: Translation of illegal for Spanish Speakers

Britannica English: Translation of illegal for Arabic Speakers


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