illegal

adjective

(ˌ)i(l)-ˈlē-gəl How to pronounce illegal (audio)
Definition of illegalnext
1
as in unlawful
contrary to or forbidden by law it is illegal to import those birds into this country

Synonyms & Similar Words

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Antonyms & Near Antonyms
2
as in foul
not being in accordance with the rules or standards of what is fair in sport an illegal pass

Synonyms & Similar Words

Antonyms & Near Antonyms

Example Sentences

Recent Examples of Synonyms for illegal
  1. unlawful
  2. foul
  3. illicit
  4. unfair
  5. criminal
  6. nasty
Adjective
  • Runa’s incarceration – and death months after her release – is now the subject of a lawsuit brought by her mother against Hyogo Prefectural Police alleging unlawful arrest and detention.
    — Hanako Montgomery, CNN Money, 24 Oct. 2026
  • Last month, the seizure was ruled unlawful by the California Supreme Court.
    — Iris Kwok, Los Angeles Times, 24 Oct. 2026
Definition of unlawful
Adjective
  • The bodies of Machado and her daughters were discovered days later after a neighbor noticed a foul odor coming from the home.
    — CBS Miami Team, CBS News, 20 Oct. 2026
  • Caminero pulled Smith’s first-pitch splitter off the left-field foul pole for a two-run homer that gave the Rays a 5-1 lead.
    — ABC News, ABC News, 19 Oct. 2026
Definition of foul
Adjective
  • So far, the most plausible driver of recent declines in overdose deaths is a change in the illicit drug supply.
    — J. Travis Donahoe, STAT, 23 Oct. 2026
  • But how and through whom the money flowed into the Alpha account revealed that it was intended to remain secret, more akin to a covert and illicit scheme, given that it was managed in part by a senior advisor to the president of the United States.
    — Matthew Cole, Vanity Fair, 22 Oct. 2026
Definition of illicit
Adjective
  • Some also called for a reform of the university admissions system, seen by many as complex and unfair.
    — Arkansas Online, Arkansas Online, 23 Oct. 2026
  • Trump has imposed new tariffs on Brazilian goods this year, including a 25% levy on some products over what the US described as unfair trade practices.
    — Alessandra Freitas, CNN Money, 23 Oct. 2026
Definition of unfair
Adjective
  • The police spokesperson said Perez was taken into custody without incident and charged with menacing and criminal possession of a weapon.
    — Iris Kwok, Los Angeles Times, 27 Oct. 2026
  • The leader of one of Haiti’s most powerful criminal organizations said the Salvadorans were killed in territory controlled by Chen Mechan, an allied gang.
    — Widlore Mérancourt, Washington Post, 26 Oct. 2026
Definition of criminal
Adjective
  • With American Family Field rocking, Ashby reared back and threw a nasty curve that Díaz tried to hold up on.
    — Jacob Lev, CNN Money, 24 Oct. 2026
  • Of course, there has been some criticism of this plan, as France is experiencing some pretty nasty civil unrest at the moment, but the game will go ahead, with the Saints having been in the country for a few days already.
    — Matt Reigle OutKick, FOXNews.com, 22 Oct. 2026
Definition of nasty
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.

Browse Nearby Words

ill-bred
illegal
illegalities
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Cite this Entry

“Illegal.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/illegal. Accessed 27 Oct. 2026.

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