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 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
  • 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
  • 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

Browse Nearby Words

Podcast

Cite this Entry

“Nefarious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/nefarious. Accessed 11 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