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 Did the nefarious villain (who may or may not have been costumed at Party City) have an accomplice within the Big Brother crew that helped facilitate the abduction? Dalton Ross, Entertainment Weekly, 6 July 2026 Fun a nefarious site preying on people’s financial insecurities through humiliating tasks? Josh Feldman, NBC news, 23 June 2026 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 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
  • Kayden Bordley, 19, faces one count each of second-degree murder and unlawful use of a weapon, and two counts of armed criminal action, according to a Jackson County charging document.
    Caroline Zimmerman, Kansas City Star, 7 July 2026
  • The hours-long pandemonium involved some teenaged children and young adults throwing mortars, fireworks and more at those who crowded about and at police officers, a grocery store getting merchandise stolen and an unlawful assembly declared.
    Sierra van der Brug, Oc Register, 6 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
  • 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
  • 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
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
  • 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
  • The congressmen and senators who support this provision should be voted out of office because Section 224 is so vile.
    Sun Sentinel Editorial Board, Sun Sentinel, 18 June 2026
Adjective
  • As its name suggests, the product is formulated with skin care superstar retinol to smooth fine lines and crow’s feet and brighten dark circles.
    Kyra Surgent, InStyle, 7 July 2026
  • El Floridita and Sloppy Joe’s, tourist destinations made famous by American novelist Ernest Hemingway, sat dark and shuttered.
    Romina Ruiz-Goiriena, USA Today, 6 July 2026
Adjective
  • That if you were deemed, as an enslaved person, if you were deemed troublesome or in some way unwanted, you would literally be sold down the river from the more northern states to the deeper south where you would potentially be treated even worse.
    Dana Taylor, USA Today, 3 July 2026
  • Offer Real Value, Not Leftovers Most product bundles fail not because the idea is bad but because the execution misses what consumers actually want.
    Expert Panel®, Forbes.com, 2 July 2026

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Cite this Entry

“Nefarious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/nefarious. Accessed 9 Jul. 2026.

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