Definition of nefariousnext
as in evil
not conforming to a high moral standard; morally unacceptable the chaste heroines and nefarious villains of old-time melodramas

Synonyms & Similar Words

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Antonyms & Near Antonyms

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How does the adjective nefarious differ from other similar words?

Some common synonyms of nefarious are corrupt, degenerate, iniquitous, vicious, and villainous. While all these words mean "highly reprehensible or offensive in character, nature, or conduct," nefarious suggests flagrant breaching of time-honored laws and traditions of conduct.

the nefarious rackets of organized crime

Where would corrupt be a reasonable alternative to nefarious?

While in some cases nearly identical to nefarious, corrupt stresses a loss of moral integrity or probity causing betrayal of principle or sworn obligations.

city hall was rife with corrupt politicians

When could degenerate be used to replace nefarious?

In some situations, the words degenerate and nefarious are roughly equivalent. However, degenerate suggests having sunk to an especially vicious or enervated condition.

a degenerate regime propped up by foreign powers

When can iniquitous be used instead of nefarious?

The words iniquitous and nefarious are synonyms, but do differ in nuance. Specifically, iniquitous implies absence of all signs of justice or fairness.

an iniquitous system of taxation

When might vicious be a better fit than nefarious?

The meanings of vicious and nefarious largely overlap; however, vicious may directly oppose virtuous in implying moral depravity, or may connote malignancy, cruelty, or destructive violence.

a vicious gangster

When would villainous be a good substitute for nefarious?

While the synonyms villainous and nefarious are close in meaning, villainous applies to any evil, depraved, or vile conduct or characteristic.

a villainous assault

Example Sentences

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.
Recent Examples of nefarious This time the central crime revolves around a severed finger that is sent to the high school, and a mysterious — potentially nefarious — new teacher captivating their children. Seija Rankin, HollywoodReporter, 25 Aug. 2026 But the use of fake accounts and impersonation here is new and shows how AI might be able to convince humans to act on its behalf for nefarious purposes. Jeremy Kahn, Fortune, 25 Aug. 2026 Data collection is presented as standard business practice, not nefarious. John Tamny, Forbes.com, 18 Aug. 2026 His mission is to keep the Ark of the Covenant out of the hands of Nazis who seek it for (needless to say) nefarious means. Declan Gallagher, Entertainment Weekly, 14 Aug. 2026 See All Example Sentences for nefarious
Recent Examples of Synonyms for nefarious
Adjective
  • As someone who isn’t a character person, the centerpiece for me is Villains Grove, which takes over the Redwood Creek Challenge Trail with projections and effects that nod to various evil characters.
    Todd Martens, Los Angeles Times, 1 Sep. 2026
  • Like Slaughterhouse–Five, Mother Night explores the shadowy line separating good and evil during wartime.
    Literary Hub, Literary Hub, 31 Aug. 2026
Adjective
  • Spires is also charged with felony unlawful possession of a firearm by a dangerous person and three misdemeanors, while Wilson is also charged with two misdemeanors, filings show.
    Meredith Colias-Pete, Chicago Tribune, 31 Aug. 2026
  • Put more bluntly, sports event contracts are protected by federal law in some parts of the country but remain vulnerable elsewhere to states deeming them unlawful.
    Michael McCann, Sportico.com, 31 Aug. 2026
Adjective
  • He was branded a heretic, in part for preaching that the nobility were immoral and so was nobility itself.
    Sarah Shachat, IndieWire, 28 Aug. 2026
  • Heilbrun was speaking to his evaluation of Clancy’s case and her understanding of what is immoral.
    NBC News, NBC news, 25 Aug. 2026
Adjective
  • My prescribed low-carb, caffeine-free diet sounded horrifying on paper, but my sinful pleasures were replaced with a tasty, high-quality, and healthy alternative that left me more energized.
    Condé Nast, Condé Nast Traveler, 10 July 2026
  • Critics also have challenged the report’s characterization of cases involving women, contending these were consensual affairs that were sinful but not abusive.
    ABC News, ABC News, 25 June 2026
Adjective
  • Your husband merely identified the obvious, most vicious enemy of the people in straightforward terms.
    Andy Andersen, Vulture, 30 Aug. 2026
  • Democrats have little trouble understanding that the right-wing infighting over Carlson is about whether the Republican tent, which already includes racists, nativists, and vicious Islamophobes, is also big enough to include anti-Semites.
    Jonathan Chait, The Atlantic, 28 Aug. 2026
Adjective
  • Disgusted that any adult would ever consider exploiting a child in such a vile and predatory way.
    Bryan Lynn, CBS News, 6 Aug. 2026
  • His tenure came to an end when video surfaced of a drunken Galliano berating other customers at a Paris bar with vile antisemitic insults.
    Greg Evans, Deadline, 1 Aug. 2026
Adjective
  • On top of the moving-camera-foamy-dark-mouth challenge, there was the plaque challenge.
    Jenny Bailly, Allure, 1 Sep. 2026
  • Finley’s breakout was the 2017 dark comedy Thoroughbreds, in which Olivia Cooke and Anya Taylor-Joy play high-schoolers conspiring to kill an abusive stepfather.
    Roxana Hadadi, Vulture, 31 Aug. 2026
Adjective
  • Poor Anton has been left out of the drama all day, an effort by Billie and Samir to prevent an already bad futzing from escalating to something severe, and that’s never where Anton likes to be.
    Ben Rosenstock, Vulture, 28 Aug. 2026
  • Although rarely seen, its reemergence earlier this summer is a signal of how bad the region’s ongoing drought has gotten, as well as a warning for the difficult months ahead.
    Andrew Paul, Popular Science, 27 Aug. 2026

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Cite this Entry

“Nefarious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/nefarious. Accessed 3 Sep. 2026.

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