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 These are among at least 10 individuals connected to sensitive US nuclear and aerospace research who have died or disappeared in recent years, prompting concerns whether they are connected and fueling speculation online about the possibility of nefarious activity. Natasha Chen, CNN Money, 21 Apr. 2026 Like every technological innovation AI going to be used for virtuous and nefarious things, but in terms of criminal activity experts say the scale and sophistication of fraud has accelerated. Phillip M. Bailey, USA Today, 17 Apr. 2026 The new season explores child stars gone bad, the death of Prince, nefarious celebrity doctors, The Jerry Springer Show, and more. K. Thor Jensen, PC Magazine, 17 Apr. 2026 When a technology company does it, the assumption is more nefarious. Jonathan Hunt, Fortune, 11 Apr. 2026 See All Example Sentences for nefarious
Recent Examples of Synonyms for nefarious
Adjective
  • Specifically, carapaces spelling out 8647, which is either shell-speak for evil intent or a bartender telling Patel to 86 his personal booze and buy a drink already.
    Pat Beall, Sun Sentinel, 8 May 2026
  • The story is built around Kitana’s childhood trauma of losing her father to the evil Shao Kahn (Martyn Ford), who has taken over her home realm of Edenia, enslaving her mother as his zombie consort, Sindel (Ana Thu Nguyen).
    Katie Walsh, Boston Herald, 8 May 2026
Adjective
  • A’Jonya Shorter, 18, is charged with dangerous possession of a firearm, a Level 5 felony; possession of a firearm on school property, a Level 6 felony; and misdemeanor unlawful carrying of a handgun.
    Meredith Colias-Pete, Chicago Tribune, 8 May 2026
  • The money, hidden in furniture, was never reported through standard police channels, prompting the former intelligence chief in 2022 to file a criminal complaint alleging a cover-up, money laundering, and unlawful use of Ramaphosa’s bodyguards to track down suspects.
    Tiisetso Motsoeneng, semafor.com, 8 May 2026
Adjective
  • Each side views members of the other party not as merely having a different view on politics but rather as evil or immoral.
    James Piazza, Twin Cities, 30 Apr. 2026
  • Pope Francis changed the church’s social teaching to declare capital punishment immoral in all cases.
    Nicole Winfield, Fortune, 23 Apr. 2026
Adjective
  • Christian moralists thundered against the sinful pleasures of watching naked female flesh at the Spectacles.
    Literary Hub, Literary Hub, 15 Apr. 2026
  • 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
Adjective
  • Connecticut led New York 13-4 through the first four minutes of the third quarter, but Stewart killed the momentum with a vicious block from behind as Miller went up for a fast-break layup off of a steal.
    Emily Adams, Hartford Courant, 9 May 2026
  • Harris’s film, though, trades brainy barbs for some pretty vicious violence as a set of twins, badly scarred from a childhood fire, go on a journey to confront the root of their trauma.
    Juan A. Ramírez, Vogue, 8 May 2026
Adjective
  • John Dickinson, one of the wealthiest colonists, warned that the vile East India Company, having devastated India, would start in on America.
    Daniel Immerwahr, New Yorker, 4 May 2026
  • The bleak tortures Ohm concocts for his characters are as vile as the Bilberry’s fetid jacuzzi.
    Amy Nicholson, Los Angeles Times, 30 Apr. 2026
Adjective
  • But what exactly happens to these baby stars next isn't always clear (literally) because they are buried deep within clouds of dark, dusty gas that obscure them.
    Keith Cooper, Space.com, 28 Apr. 2026
  • All the bedrooms can be found upstairs, including one that’s currently being used as an office and a primary suite flaunting dual dressing rooms and baths, plus a sauna clad in dark gray stone.
    Wendy Bowman, Robb Report, 28 Apr. 2026
Adjective
  • Or worse, to turn it into a sort of prison sentence.
    James Wood, New Yorker, 4 May 2026
  • Still, from his horns and tattoos to the double-bladed lightsaber, Maul's bad-guy chic was hard to beat.
    Brian Truitt, USA Today, 3 May 2026

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Cite this Entry

“Nefarious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/nefarious. Accessed 10 May. 2026.

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