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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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 Although that's not explicitly nefarious, Geekbench notes that with so few games and apps currently supported, the Intel BOT could misrepresent what the new chips can do. Jon Martindale, PC Magazine, 1 Apr. 2026 The leak could also give hackers a major leg up in their efforts to identify exploitable software vulnerabilities — or find new ways to arm their own instances of Claude Code for nefarious purposes. Victor Tangermann, Futurism, 1 Apr. 2026 Certainly, the association with Jeffrey Epstein is not especially helpful for debunking something nefarious. Mike Rothschild, Big Think, 31 Mar. 2026 Surely not everyone’s dips are related to nefarious misrepresentations, as evidenced by the 47 players who gained height through this process, though only two went up more than one inch. Sam Blum, New York Times, 30 Mar. 2026 See All Example Sentences for nefarious
Recent Examples of Synonyms for nefarious
Adjective
  • Besides, anyone who doesn’t agree with the left is said to be evil, so anything progressives do to destroy, or at least restrain that evil, is justified.
    Chris Roemer, Baltimore Sun, 9 Apr. 2026
  • Fifteen years later, her sister Merry faces her family’s dark past with a journalist uncovering the nature of the evil force that undid them.
    Rebecca Rubin, Variety, 9 Apr. 2026
Adjective
  • Under Texas law, a contract signed under duress is generally voidable if it was obtained through an improper or unlawful threat that overrode the signer’s free will.
    Chase Rogers, Dallas Morning News, 10 Apr. 2026
  • Violating that trust is both cruel and unlawful.
    DeJanay Booth-Singleton, CBS News, 10 Apr. 2026
Adjective
  • Lawyers for the church argue that Morris’ agreements with the church preclude him from those benefits if he was fired or resigned because of immoral behavior.
    Lillie Davidson, Fort Worth Star-Telegram, 2 Apr. 2026
  • The Michigan State Police said Robert Wilson, 44, of Gaylord, was arrested on March 25 and lodged at the Otsego County Jail on one charge each of accosting a minor for immoral purposes and using a computer to commit a crime.
    Paula Wethington, CBS News, 27 Mar. 2026
Adjective
  • His father, who believes Sammie's music to be sinful, orders him to drop the guitar, but Sammie can't do it.
    Randall Colburn, Entertainment Weekly, 12 Mar. 2026
  • The least sinful states in 2026 Wyoming was ranked the least sinful state in 2026, followed by New Hampshire, Idaho, Vermont, Maine, Minnesota, Utah, Iowa, Nebraska and South Dakota.
    Alexis Simmerman, Austin American Statesman, 25 Feb. 2026
Adjective
  • The wereboar growled next to Black Pudding, a hulking vicious monster, both focused on ripping Puck and Cordelia to shreds.
    Jaclyn Cosgrove, Los Angeles Times, 10 Apr. 2026
  • The childishness of his expressions infantilized a genuinely vicious regime, painting it as more peevish than petrifying.
    Fintan O’Toole, The New York Review of Books, 9 Apr. 2026
Adjective
  • His Max is both vile and charming, and the result is undeniably magnetic.
    Shania Russell, Entertainment Weekly, 7 Apr. 2026
  • Slayyyter’s music is vile, explicit, and a threat to common decency.
    Harry Tafoya, Pitchfork, 2 Apr. 2026
Adjective
  • Sunscreen protects against sun damage, premature aging and dark spots.
    Lauren Jarvis-Gibson, Fort Worth Star-Telegram, 8 Apr. 2026
  • Harden, 36, with his famous, protruding beard and those dark, piercing eyes, was determined to use his star power to get his way, to bring with him a slice of comfort to a new city.
    Joe Vardon, New York Times, 7 Apr. 2026
Adjective
  • Gas and diesel prices have soared since the start of the Iran war, but the situation could get even worse later this year because of ethanol requirements and problems with fertilizer supply chains.
    E.J. Antoni, Boston Herald, 6 Apr. 2026
  • Flattening the curve—making bad floods somewhat less bad—feels achievable.
    Eric Klinenberg, New Yorker, 6 Apr. 2026

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Cite this Entry

“Nefarious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/nefarious. Accessed 13 Apr. 2026.

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