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 Back then, this information was a literal document, something that could be tangibly stored in a safe space and kept away from any nefarious or ill-intentioned parties. William Jones, USA Today, 3 June 2026 Be it getting hit by a car, taken by predators, or snatched up for nefarious reasons like being used for dog fights. Stephen Underwood, Hartford Courant, 2 June 2026 Captain Jonathan Baxter told PEOPLE that the surfer's death was not caused by anything nefarious. Charna Flam, PEOPLE, 29 May 2026 LLMs can be poisoned and forced to hallucinate, or they can also be jailbroken and used for nefarious purposes. Tom Kellermann, Forbes.com, 28 May 2026 See All Example Sentences for nefarious
Recent Examples of Synonyms for nefarious
Adjective
  • Zoroastrianism’s core tenets – a single God, the cosmic struggle between good and evil – are widely believed by historians to have formed the theological groundwork for the major Abrahamic religions.
    Rhea Mogul, CNN Money, 21 June 2026
  • Not all devices are evil, the toys realize, and even the best machines—like even the best toys—will eventually break down and get tossed aside for a shiny new model.
    Justin Chang, New Yorker, 19 June 2026
Adjective
  • The filing, submitted in the San Diego County Superior Court, seeks a judge’s order to condemn and destroy the embargoed kratom products, halt ongoing unlawful manufacturing and impose civil penalties.
    Karen Garcia, Los Angeles Times, 19 June 2026
  • Justice Neil Gorsuch wrote in the court's opinion that unlawful drug use alone cannot be grounds to seek to send someone to prison and potentially force them to give up firearms for life.
    Devin Dwyer, ABC News, 18 June 2026
Adjective
  • These monsters—its antitheses—constitute that part of our nature that urges us to be sensible and strong, and that inclines us to see the life drive as trivial, weak, sentimental and immoral.
    Literary Hub, Literary Hub, 17 June 2026
  • The artist wrote that keeping silent on this kind of behavior is akin to turning a blind eye to immoral behavior.
    Kory Grow, Rolling Stone, 16 June 2026
Adjective
  • Naim and his overly anxious single mom (Mia Wasikowska) attend rote church services in which the pastor looks to exorcise the LGBTQ+ from sinful boys who like boys and girls who like girls.
    Randy Myers, Mercury News, 18 June 2026
  • Bowing down and worshiping an idol is sinful.
    Lauren Costantino, Miami Herald, 12 May 2026
Adjective
  • The story follows vicious ex-con, Max Cady (Bardem) and his revenge plot against married couple Tom (Patrick Wilson) and Anna Bowden (Adams).
    Erik Kain, Forbes.com, 19 June 2026
  • Mahmic’s vicious goal in traffic salvaged some good feeling before a decisive showdown with Qatar next week.
    ABC News, ABC News, 18 June 2026
Adjective
  • Powerful, rich people filled the lawn to watch a violent sport that ended with a vile and racist comment.
    Ryan Coleman, Entertainment Weekly, 16 June 2026
  • That person is referring to heavyweight Josh Hokit, who is facing widespread backlash for making a vile joke about former first lady Michelle Obama after winning his match over Derrick Lewis.
    Martha Ross, Mercury News, 15 June 2026
Adjective
  • But the true story behind it is a dark, sad and overall pretty confusing one.
    Nick Miller, New York Times, 17 June 2026
  • Trudeau embraced the Southern California vibes and wore a green T-shirt with black shorts and a pair of dark sunglasses.
    Tracy Wright, FOXNews.com, 16 June 2026
Adjective
  • Are those still your worst fears?
    Emily Nussbaum, New Yorker, 21 June 2026
  • While a higher tracker error is not bad in and of itself, most investors become uncomfortable when their portfolio acts so differently from the index.
    Bill Stone, Forbes.com, 21 June 2026

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Cite this Entry

“Nefarious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/nefarious. Accessed 23 Jun. 2026.

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