Synonyms of illicit

illicit

adjective

(ˌ)i(l)-ˈli-sət 

as in illegal

contrary to or forbidden by law

had a long history of using illicit drugs

Synonyms & Similar Words

• illegal
• unlawful
• criminal
• felonious
• unauthorized
• wrongful
• forbidden
• illegitimate
• prohibited
• lawless
• immoral
• sinful
• criminalized
• evil
• unethical
• shameful
• wrong
• wicked
• unsanctioned
• bad
• unlicensed
• contraband
• reprehensible
• proscribed
• under-the-table
• outlawed
• unscrupulous
• blameworthy
• corrupt
• discouraged
• barred
• disallowed
• censurable
• interdicted
• banned
• villainous
• unprincipled
• under-the-counter
• bootleg
• blamable
• adulterine

Antonyms & Near Antonyms

• legal
• legitimate
• lawful
• good
• ethical
• right
• permitted
• righteous
• virtuous
• just
• authorized
• principled
• licensed
• approved
• endorsed
• proper
• correct
• allowed
• promoted
• supported
• sanctioned
• decent
• suggested
• encouraged
• abetted
• decorous
• seemly

Example Sentences

Recent Examples of illicit

In response to pressure from trade associations, law enforcement and major retail chains, regulatory authorities and e-commerce platforms, verification mechanisms have been tightened to dismantle illicit pipelines. — Arthur Zaczkiewicz, Footwear News, 19 Oct. 2026

From December 2024 to May 2025, the international law enforcement body Interpol conducted Operation Pangea XVII, in which authorities in 90 countries seized more than 50 million doses of illicit pharmaceuticals. — Andrew Yockey, Fortune, 15 Oct. 2026

Participants were also asked about their alcohol consumption, smoking and illicit drug use. — New Atlas, 14 Oct. 2026

Wildlife is believed to travel through a series of border crossings linking Thailand and Myanmar, including the Mae Sot-Myawaddy and Tachileik-Mae Sai corridors, both of which have long been associated with all manner of illicit trafficking. — Rhea Mogul, CNN Money, 14 Oct. 2026