nefarious

adjective

ne·​far·​i·​ous ni-ˈfer-ē-əs 

: flagrantly wicked or impious : evil

nefariously adverb

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What Is the Difference Between vicious, villainous, and nefarious?

Nefarious comes from the Latin adjective nefarius and the Latin noun nefas, which means "crime." Nefas is a combination of ne- ("not") and fas, meaning "right" or "divine law."

Synonyms

• evil
• unlawful
• immoral
• sinful
• vicious
• vile
• dark
• bad
• wicked
• villainous

Choose the Right Synonym for nefarious

vicious, villainous, iniquitous, nefarious, corrupt, degenerate mean highly reprehensible or offensive in character, nature, or conduct.

vicious may directly oppose virtuous in implying moral depravity, or may connote malignancy, cruelty, or destructive violence.

a vicious gangster

villainous applies to any evil, depraved, or vile conduct or characteristic.

a villainous assault

iniquitous implies absence of all signs of justice or fairness.

an iniquitous system of taxation

nefarious suggests flagrant breaching of time-honored laws and traditions of conduct.

the nefarious rackets of organized crime

corrupt stresses a loss of moral integrity or probity causing betrayal of principle or sworn obligations.

city hall was rife with corrupt politicians

degenerate suggests having sunk to an especially vicious or enervated condition.

a degenerate regime propped up by foreign powers

Examples of nefarious in a Sentence

Moreover, those starry-eyed states inclined to perceive international relations in moral terms frequently underestimate the nefarious machinations of their competitors on the world political stage. —Richard Wolin, New Republic, 4 June 2001

… I always give the same response: Just because Frank posed for pictures with every leading capo, underboss and cement contractor of the day doesn't mean that he joined them in their nefarious underworld activities. Oh, occasionally he rode along on a hit or two, but that was just one of those social obligations … —Lewis Grossberger, Time, 21 Dec. 1998

Three-tenths of a mile uphill from our mailbox on the road, that bend is so nefarious that neophytes often skidded into a snowbank or wound up fender-deep in mud there. —Maxine Kumin, In Deep, 1987

a nefarious scheme to cheat people out of their money

the chaste heroines and nefarious villains of old-time melodramas

Recent Examples on the Web

But Trump and Hassett provided no evidence of anything nefarious taking place at the BLS. —David Goldman, CNN Money, 5 Aug. 2025

But don't worry, Google doesn't use the data for nefarious purposes like selling it to third parties to line its pockets. —Kurt Knutsson, FOXNews.com, 5 Aug. 2025

Cena did not change anything about himself and blamed the fans for his newly nefarious ways. —Alfred Konuwa, Forbes.com, 4 Aug. 2025

In essence, according to this argument, 3I/ATLAS could have been sent by a hidden and nefarious alien force somewhere out in the galaxy, perhaps to spy on humans. —Adam Carlson, People.com, 30 July 2025

Word History

Etymology

Latin nefarius, from nefas crime, from ne- not + fas right, divine law; perhaps akin to Greek themis law, tithenai to place — more at do

First Known Use

1567, in the meaning defined above

Rhymes for nefarious

• aquarius
• cinereous
• gregarious
• hilarious
• malarious
• precarious
• vicarious
• carious
• scarious
• various
• multifarious

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Kids Definition

nefarious

adjective

ne·​far·​i·​ous ni-ˈfar-ē-əs 

-ˈfer-

: very wicked : evil

nefariously adverb

nefariousness noun