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 These nefarious little nannies were blamed for every cool model that didn’t make it to our shores, and every sweet performance option left on the table (not to mention every part that fell off of an American car built between 1979 and 1999). Byron Hurd, The Drive, 5 Aug. 2026 That's not to suggest Ohio State or any of Smith's other finalists did anything nefarious. Austin Perry Outkick, FOXNews.com, 30 July 2026 Downey will star in Doomsday — though this time as the nefarious Victor Von Doom/Doctor Doom. Emlyn Travis, Entertainment Weekly, 26 July 2026 Because Wells was not with his friends and didn’t have his phone, his parents suspect something more nefarious could have happened and been covered up. Adam Carlson, PEOPLE, 23 July 2026 See All Example Sentences for nefarious
Recent Examples of Synonyms for nefarious
Adjective
  • Bannister starred in all five Phantasm films, battling the evil Tall Man, a role that cemented his place in horror cinema.
    Tim Lammers, Forbes.com, 11 Aug. 2026
  • Despite the very best efforts of writers, cast and crew, Rhaenyra, her evil half-brothers and all their fellow citizens were never Martin’s main characters.
    Lorraine Ali, Los Angeles Times, 10 Aug. 2026
Adjective
  • Greg Field, a 27-year LAPD veteran and director of the Police Transportation Motor Transport Division, noted the sync systems are useful for mass messages, such as at a fire evacuation or an unlawful assembly.
    Andrew J. Campa, Los Angeles Times, 10 Aug. 2026
  • McFadden is currently charged with unauthorized use of a motor vehicle, robbery, and unlawful possession of a firearm.
    Matthew Ablon, CBS News, 10 Aug. 2026
Adjective
  • Neither Agamemnon nor Menelaus grasp that their actions toward their wives were immoral.
    Roxana Hadadi, Vulture, 29 July 2026
  • Some rabbinic readings attribute Lot’s hesitation to leave Sodom to his immoral greed and inordinate wealth.
    Encyclopedia Britannica, Encyclopedia Britannica, 2 July 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
  • And on the other side of the ball, this defense has a chance to be downright vicious.
    Dieter Kurtenbach, Mercury News, 12 Aug. 2026
  • Heidegger, the philosopher of authenticity and independent thought, had become one of them, surrendering to vicious political cant.
    David Denby, New Yorker, 10 Aug. 2026
Adjective
  • Disgusted that any adult would ever consider exploiting a child in such a vile and predatory way.
    Bryan Lynn, CBS News, 6 Aug. 2026
  • His tenure came to an end when video surfaced of a drunken Galliano berating other customers at a Paris bar with vile antisemitic insults.
    Greg Evans, Deadline, 1 Aug. 2026
Adjective
  • In Helaena’s room, Rhaenyra finds a tapestry Helaena had just finished sewing that predicts a dark and fiery end for Rhaenyra in the future.
    Jennifer Maas, Variety, 10 Aug. 2026
  • For somewhere closer to home, check a light pollution map and head to an area that looks dark.
    Jamie Carter, Forbes.com, 10 Aug. 2026
Adjective
  • The last war, which began in 2014, left Yemen facing one of the world’s worst humanitarian crises.
    Sophia Saifi, CNN Money, 7 Aug. 2026
  • Even worse, Brooks directed him to contact his agent instead.
    Tom Smyth, Vulture, 6 Aug. 2026

Browse Nearby Words

Podcast

Cite this Entry

“Nefarious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/nefarious. Accessed 13 Aug. 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