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 While acknowledging the risk posed by recent security breaches, some analysts said the identification of cyber vulnerabilities could help companies address the problems before a nefarious actor moves to exploit them. Max Zahn, ABC News, 11 Aug. 2026 What first appears to be a run-of-the-mill Seattle rainstorm is soon revealed to be something more nefarious, as the apparently sentient precipitation seals everyone inside of their homes. David Ehrlich, IndieWire, 7 Aug. 2026 That’s not to say the government needs proof to exercise autonomy over what to do with our bodies, but perhaps there was a more nefarious plot at play when the ban that propels One Night Only came into being. Fran Hoepfner, Vulture, 7 Aug. 2026 While a young child predicting that robots will one day do their homework might seem pretty innocuous, the same kind of tools can be used for far more nefarious purposes. Victor Tangermann, Futurism, 6 Aug. 2026 See All Example Sentences for nefarious
Recent Examples of Synonyms for nefarious
Adjective
  • She’d been told that people outside her faith were evil, and yet her pastor’s wife had turned her away while these scientists were literally bending over to help her.
    Felice J. Freyer, STAT, 19 Aug. 2026
  • Still, there is much old-school horror fun to be had here, with costume designer Liz Keogh Palmer and the team of makeup artists especially deserving of credit with their mind-blowing work on various evil spirits.
    Tomris Laffly, Variety, 19 Aug. 2026
Adjective
  • The party also viewed Yabloko’s stance on Ukraine as unlawful and tantamount to calling for the violation of Russia’s territorial integrity.
    CNN Money, CNN Money, 18 Aug. 2026
  • The duo and two others, Mohammed Hurabi and Lars Zeepvat, were hit with the worst charges — felony corrupt organizations, conspiracy, dealing in proceeds of unlawful activity, and other related offenses.
    Brady Knox, The Washington Examiner, 17 Aug. 2026
Adjective
  • When Russians embrace the Eurasian narrative, they are also engaged in the political project of rejecting Europe and the West, which Putin and his allies deride as decadent, declining, and immoral.
    Foreign Affairs, Foreign Affairs, 18 Aug. 2026
  • In the realms of art, literature, film, and television, words and images that would once have been considered indecent, offensive, or immoral are now commonplace, especially in the West.
    Literary Hub, Literary Hub, 12 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
  • But Roy’s story of Annie (Arjun Raina), a New Delhi architecture student caught in a vicious cycle of failing and repeating his studies, gradually reveals itself as a sharp and poignant portrayal of youth, deftly poised between hope and cynicism.
    Jill Goldsmith, Deadline, 18 Aug. 2026
  • Lawsuits, bureaucratic battles, boisterously divisive council arguments and vicious social media debates have been part of Bloomfield life for years, and intensified during Danielle Wong’s contentious time as mayor.
    Don Stacom, Hartford Courant, 18 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
  • Things take a dark turn, however, after a series of unexplainable deaths draw Hal and John to a small town in Nebraska.
    Matt Minton, Variety, 17 Aug. 2026
  • Way back in 2012, Supreme collaborated on another Air Force 1 with a dark green camo canvas upper, box logo hangtag and gum outsole that can hit the $1,000 range on resale platforms.
    Ian Servantes, Footwear News, 17 Aug. 2026
Adjective
  • Sensing a disconnect or worse, a feeling of being forgotten, Campbell this summer invited some of the men who wrote those letters to campus.
    Dana O’Neil, CNN Money, 14 Aug. 2026
  • Dry weather periods are expected in Colorado, and wildfires tend to be worse during these times.
    Callie Zanandrie, CBS News, 14 Aug. 2026

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Cite this Entry

“Nefarious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/nefarious. Accessed 21 Aug. 2026.

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