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 However, experts caution that there is no data to show how well the tool works to detect nefarious logins or malicious activity. Ashley Belanger, ArsTechnica, 13 Aug. 2026 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 See All Example Sentences for nefarious
Recent Examples of Synonyms for nefarious
Adjective
  • Presumably everybody wants the evidence to hold people who commit serious crimes accountable, but nobody wants to turn into the evil empire in the process.
    Jack Dolan, Los Angeles Times, 26 Aug. 2026
  • Her parents refuse to see that there is something unnatural about their new baby boy and that an evil other presence haunts their stately home.
    Tanya Fedak, Variety, 26 Aug. 2026
Adjective
  • Legal experts say such a move would probably be swiftly blocked by courts, as would any unlawful deployment of military troops to polls.
    Kevin Rector, Los Angeles Times, 23 Aug. 2026
  • The suit alleges that Paramount’s unlawful termination has caused him some $4 million in economic damages.
    Gene Maddaus, Variety, 21 Aug. 2026
Adjective
  • Heilbrun was speaking to his evaluation of Clancy’s case and her understanding of what is immoral.
    NBC News, NBC news, 25 Aug. 2026
  • According to experts, this device could rot my brain, influence me to commit immoral acts, and even ruin my eyesight.
    Literary Hub, Literary Hub, 21 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
  • Detectives charged him with murder, manslaughter and criminal possession of a weapon for the vicious attack that killed his mother, 57-year-old Josefa Soto de Guzman, on Friday.
    Colin Mixson, New York Daily News, 26 Aug. 2026
  • Pace, skill, a vicious shot, the ability to make opposition defenders look like fools.
    James Horncastle, New York Times, 26 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
  • The design featured an orange-and-black clown outfit, black gloves and a dark face covering with an exaggerated smiling mouth.
    Rosemary Feitelberg, Footwear News, 24 Aug. 2026
  • Funky black garlic hides within that mushroom melange, and the pie arrives dotted with a dramatic, dark tamarind sauce.
    The Bon Appétit Staff, Bon Appetit Magazine, 24 Aug. 2026
Adjective
  • Neighbors said the rotten-egg smell has gotten worse over the last couple of weeks, even trailing to apartments across the street.
    Nicole Comstock, CBS News, 21 Aug. 2026
  • For Panama, the result is a wet season that’s already been drier than usual and is likely to get worse.
    Hira Humayun, CNN Money, 21 Aug. 2026

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Cite this Entry

“Nefarious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/nefarious. Accessed 27 Aug. 2026.

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