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adjective ne·far·i·ous \ni-ˈfer-ē-əs\

Simple Definition of nefarious

  • : evil or immoral

Source: Merriam-Webster's Learner's Dictionary

Full Definition of nefarious

  1. :  flagrantly wicked or impious :  evil



Examples of nefarious in a sentence

  1. 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

  2. … 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

  3. 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

  4. a nefarious scheme to cheat people out of their money

  5. <the chaste heroines and nefarious villains of old-time melodramas>

Did You Know?

Vicious and "villainous" are two wicked synonyms of "nefarious," and, like "nefarious," both mean "highly reprehensible or offensive in character, nature, or conduct." But these synonyms are not used in exactly the same way in all situations. "Vicious" may imply moral depravity or it may connote malignancy, cruelty, or destructive violence. "Villainous" applies to any evil, depraved, or vile conduct or characteristic, while "nefarious" (which derives from the Latin noun nefas, meaning "crime") suggests flagrant breaching of time-honored laws and traditions of conduct. "Nefarious" first appeared in English in the early 17th century, whereas "vicious" and "villainous" preceded "nefarious" by about two hundred years.

Origin and Etymology of nefarious

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: circa 1609

Synonym Discussion of 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>.

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