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

Relevance

Antonyms & Near Antonyms

Synonym Chooser

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 But the movie also understands that this impulse isn’t always a nefarious one. Brianna Zigler, Entertainment Weekly, 15 July 2026 But the others have each been marked by some kind of controversy caused by the supposedly nefarious actions of an Argentina player. Nick Miller, New York Times, 14 July 2026 Prosecutors told jurors at trial that the group's actions — including bringing firearms, first aid kits and wearing body armor — were signals of nefarious intent. Steven Rosenbaum, CBS News, 1 July 2026 Prosecutors told jurors at trial that the group’s actions — including bringing firearms, first aid kits and wearing body armor — signaled nefarious intent. Jamie Stengle, Los Angeles Times, 1 July 2026 See All Example Sentences for nefarious
Recent Examples of Synonyms for nefarious
Adjective
  • In addition to the Griffins’ evil-genius toddler son, MacFarlane will voice Bean, Stewie’s man-of-very-few-words classmate who was dropped on his head one too many times.
    Nellie Andreeva, Deadline, 22 July 2026
  • With the franchise’s trademark blend of extreme gore and dark humor, the Evil Dead backstory centers on the ancient Book of the Dead that unleashes supernatural evil forces and twists victims into sadistic, shape-shifting, near-invincible monsters.
    Brady MacDonald, Oc Register, 21 July 2026
Adjective
  • Since the tournament began, police have declared unlawful assemblies twice, including late July 5, when a crowd began throwing bottles at officers.
    Ryan Macasero, Mercury News, 19 July 2026
  • Opponents counter that California already bars unlawful firearm manufacturing with 3-D printers, and that ghost gun recoveries have declined since the state adopted a series of new laws and enforcement efforts.
    Los Angeles Times, Los Angeles Times, 19 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
  • Harbaugh had tense standoffs with legacy defenders Ed Reed, Ray Lewis and Terrell Suggs and, during the 2012 season, held a sitdown with his players to address their vicious and personal attacks on his approach.
    Ian O'Connor, New York Times, 22 July 2026
  • The film also shows Maddox and her father in a vicious argument inside her car that illustrates the fracturing of their once-close bond.
    Los Angeles Times, Los Angeles Times, 22 July 2026
Adjective
  • Here, though, the entire enterprise is vile, and futile, and irredeemable, made worse by the self-delusion of the people who pursue it.
    Paul A. Thompson, Pitchfork, 21 July 2026
  • Finally, if companies like Hilton are going to investigate and fire every employee who posts something vile online, the workforce could become noticeably thinner.
    Bobby Burack OutKick, FOXNews.com, 15 July 2026
Adjective
  • Skywatchers should find dark locations and look north, as the aurora's intensity also hinges on the solar wind's magnetic field orientation.
    Jamie Carter, Forbes.com, 21 July 2026
  • And in a dark time for the world, a magnificent tournament helped make the world feel a little smaller.
    David Goldman, CNN Money, 20 July 2026
Adjective
  • Shouldn’t Tamra take that as a sign to repair her relationships with the women rather than alienate the one person who is willing to look past her bad behavior?
    Brian Moylan, Vulture, 17 July 2026
  • That statistic shows that hotels did worse with the World Cup than without it initially.
    Miami Herald, Miami Herald, 17 July 2026

Browse Nearby Words

Podcast

Cite this Entry

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

More from Merriam-Webster on nefarious

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

More from Merriam-Webster