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 Reddit already blocks an average of 100,000 nefarious accounts each day, and those that don’t pass the new verification system may be restricted. Jibin Joseph, PC Magazine, 26 Mar. 2026 Don’t see us as a nefarious force. Staff Artist, Dallas Morning News, 26 Mar. 2026 Fox and Shepherd believe something more nefarious happened to Aujay. Madison Dapcevich, Outside, 21 Mar. 2026 Prosecutor Shawn Smith told jurors during closing arguments that the group’s actions — including bringing firearms and first aid kits and wearing body armor — were all signs of nefarious intent. Jamie Stengle, Los Angeles Times, 14 Mar. 2026 See All Example Sentences for nefarious
Recent Examples of Synonyms for nefarious
Adjective
  • After tracking it down almost two decades later, Prince Adam is whisked back across space to defend his home planet against the evil forces of Skeletor.
    Glenn Garner, Deadline, 28 Mar. 2026
  • Black is reprising his role as the sassy, if evil, Bowser in the sequel.
    Amaris Encinas, USA Today, 28 Mar. 2026
Adjective
  • Heifler was charged with ferdeal counts of unlawful possession of a destructive devices and unlawful making of destructive devices, officials said.
    Rocco Parascandola, New York Daily News, 27 Mar. 2026
  • Stanford School of Medicine prohibits unlawful discrimination on the basis of race, color, national or ethnic origin, or any other characteristic protected by applicable law.
    Mary Kekatos, ABC News, 27 Mar. 2026
Adjective
  • 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
  • When the status quo is fundamentally evil and dysfunctional, then Trimming is immoral.
    David Brooks, The Atlantic, 25 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
  • Surrounded by vicious and violent hitmen that have been pressed into service as childcare, Juan Pablo must reckon with his father's crumbling power and find his own way in the world after his death.
    K. Thor Jensen, PC Magazine, 27 Mar. 2026
  • This vicious cycle increases until the energy is released essentially in an explosion.
    Phil Plait, Scientific American, 27 Mar. 2026
Adjective
  • Cinderella with one vile stepsister would be locked in a zero-sum game.
    Christine Smallwood, Harpers Magazine, 24 Mar. 2026
  • Other presidents have been partisan; other presidents have exhibited vile behavior.
    Jonathan Lemire, The Atlantic, 21 Mar. 2026
Adjective
  • On the last night that anybody else reportedly saw Nancy, that camera caught a glimpse of a person clad in dark clothes, wearing gloves and a black balaclava, unidentifiable, standing at the threshold.
    Vinson Cunningham, New Yorker, 1 Apr. 2026
  • Not only did that article form the basis of the film, but Lumet actually took the note and cast Pacino in the role of that dark, thin fellow.
    Chris Jones, New York Daily News, 31 Mar. 2026
Adjective
  • Bernadine appeared to be useless—or, worse, a potential double agent.
    David D. Kirkpatrick, New Yorker, 30 Mar. 2026
  • This is very bad for our health.
    Peter D'Oench, CBS News, 30 Mar. 2026

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Cite this Entry

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

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