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 Along the way, gamers will investigate strange planets, derelict spaceships, Remnant Era Celestial technology, and the nefarious posthumans. Jeff Spry, Space.com, 16 June 2026 Amazingly, Richard Nixon, the most nefarious American political personality of the 1970s, appears to be making a comeback, at least online. Benjamin Svetkey, HollywoodReporter, 16 June 2026 These are just underlying stylistic facts of how the teams play, not some nefarious plot to favor a big and important market such as New York. John Hollinger, New York Times, 10 June 2026 Some residents have worried the mysterious explorers captured on video were up to something nefarious. ABC News, 4 June 2026 See All Example Sentences for nefarious
Recent Examples of Synonyms for nefarious
Adjective
  • Through Latin and early Christian usage, the word took on its modern sense of an evil supernatural spirit.
    Erik Kain, Forbes.com, 8 July 2026
  • When it was overturned, however, the United States rightly or wrongly became the evil empire to the rest of world soccer.
    Mark Sappenfield, Christian Science Monitor, 7 July 2026
Adjective
  • Federal authorities routinely target South Florida remittance companies that operate as conduits for unlawful money transfers, especially for drug traffickers, because many are suspected of evading bank-reporting requirements.
    Jay Weaver, Miami Herald, 10 July 2026
  • Renner was charged with second-degree manslaughter and Seymore with unlawful imprisonment, among other charges.
    Megan Fahrney, ABC News, 10 July 2026
Adjective
  • Some rabbinic readings attribute Lot’s hesitation to leave Sodom to his immoral greed and inordinate wealth.
    Encyclopedia Britannica, Encyclopedia Britannica, 2 July 2026
  • Court records show that 60-year-old Bradley Kyle Martin, of Dearborn Heights, is charged with using a computer or internet to communicate with another person to commit a crime and accosting children for immoral purposes.
    DeJanay Booth-Singleton, CBS News, 25 June 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
  • The early Cold War liberals had read their history books and seen how the French Revolution had begun with high progressive hopes but descended into a vicious bloodbath.
    David Brooks, The Atlantic, 8 July 2026
  • After a similarly vicious storm struck the New York area late Friday, hundreds of thousands of utility customers were left without power, trains to New Jersey were canceled and thousands of trees were damaged or uprooted.
    Los Angeles Times, Los Angeles Times, 4 July 2026
Adjective
  • Earlier in the week, after France’s bruising win over Paraguay, a Paraguayan senator launched into a series of vile and racist attacks against Mbappé, questioning his intelligence, his manners, and even his Frenchness.
    Louisa Thomas, New Yorker, 10 July 2026
  • Frazier eagerly reposted a vile lie claiming Israelis drop bombs disguised as toys to murder children—originally posted by a UK activist facing terror charges for backing Hamas.
    Staff, FOXNews.com, 2 July 2026
Adjective
  • Aerial footage showed heavy damage to the suspect's vehicle, a dark gray sedan.
    Dean Fioresi, CBS News, 14 July 2026
  • They're headed to a battery recycler who will shred them into a fine, dark powder called black mass, from which those minerals can be recovered and reused in new batteries.
    Camila Domonoske, NPR, 13 July 2026
Adjective
  • Despite concerns that California’s costs and regulations are bad for business, the state has attracted an unprecedented pile of capital this year, and no other state is even close.
    Los Angeles Times, Los Angeles Times, 10 July 2026
  • The Giants are now 39-54 this season, two games up on Colorado (38-57) for the worst record in the NL and second-worst in MLB.
    Christian Babcock, Mercury News, 10 July 2026

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Cite this Entry

“Nefarious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/nefarious. Accessed 15 Jul. 2026.

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