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Showing results for illicit. Search instead for illicit drug.
Synonyms

illicit

American  
[ih-lis-it] / ɪˈlɪs ɪt /

adjective

  1. not legally permitted or authorized; unlicensed; unlawful.

    Synonyms:
    prohibited, illegitimate
  2. disapproved of or not permitted for moral or ethical reasons.


illicit British  
/ ɪˈlɪsɪt /

adjective

  1. another word for illegal

  2. not allowed or approved by common custom, rule, or standard

    illicit sexual relations

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Synonym Usage

See illegal.

Other Word Forms

Etymology

Origin of illicit

First recorded in 1645–55; from Latin illicitus, equivalent to il- 2 + licit ( def. )

Compare meaning

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Explanation

Illicit means not allowed by law or custom. It's illegal to kill endangered elephants, but many poachers still engage in the Illicit ivory trade. Illicit usually refers to something that is not morally proper or acceptable. Illicit activities — like smuggling or counterfeiting — happen under the radar of the law. Illicit is from Latin illicitus, from the prefix in-, "not," plus licitus, "lawful."

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Vocabulary lists containing illicit

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.

See Examples For:

Sun says Tron has innovated new collaborations with law enforcement to tackle illegal transactions on the blockchain, leading to huge declines in illicit volume on the platform.

From BBC Jul. 10, 2026

Interpol Secretary Valdecy Urquiza said human trafficking remained "one of the most profitable and pervasive forms" of organised crimes, generating billions in illicit revenue each year.

From BBC Jul. 6, 2026

L.A.’s love of fireworks makes for a colorful Fourth of July, with dozens of official celebrations and countless illicit explosions expected for the holiday.

From Los Angeles Times Jul. 4, 2026

Obrokta denied making the comment and said he never gave any illicit benefits to any player.

From The Wall Street Journal Jun. 28, 2026

As it is, this illicit reading of mine seems a kind of performance.

From "The Handmaid's Tale" by Margaret Atwood

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