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nefarious

[ni-fair-ee-uh s]
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adjective
  1. extremely wicked or villainous; iniquitous: a nefarious plot.

Origin of nefarious

1595–1605; < Latin nefārius wicked, vile, equivalent to nefās offense against divine or moral law (ne- negative prefix + fās law, right) + -ius -ious, with intervocalic s > r
Related formsne·far·i·ous·ly, adverbne·far·i·ous·ness, nounun·ne·far·i·ous, adjectiveun·ne·far·i·ous·ly, adverbun·ne·far·i·ous·ness, noun

Synonyms

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flagitious, heinous, infamous; vile, atrocious, execrable.

Antonyms

good, honest.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for nefariousness

Historical Examples

  • Mary gratified her eager mind by careful studies in this chosen line of nefariousness.

    Within the Law

    Marvin Dana

  • There was a nefariousness about the new suggestion that proved very attractive in Blentmouth.

    Tristram of Blent

    Anthony Hope

  • The nefariousness of the scheme thus revealed infuriated Barmouth.


British Dictionary definitions for nefariousness

nefarious

adjective
  1. evil; wicked; sinful
Derived Formsnefariously, adverbnefariousness, noun

Word Origin

C17: from Latin nefārius, from nefās unlawful deed, from not + fās divine law
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for nefariousness

nefarious

adj.

c.1600, from Latin nefarius "wicked, abominable, impious," from nefas "crime, wrong, impiety," from ne- "not" (see un-) + fas "right, lawful, divinely spoken," related to fari "to speak" (see fame (n.)). Related: Nefariously.

Online Etymology Dictionary, © 2010 Douglas Harper