[1] : The Collaborative International Dictionary of English v.0.48

nefarious \nefa"rious\, a. l. nefarius, fr. nefas crime,
   wrong; ne not + fas divine law; akin to fari to speak. see
   no, adv., and fate.
   wicked in the extreme; abominable; iniquitous; atrociously
   villainous; execrable; detestably vile.
   1913 webster

   syn: iniquitous; detestable; horrible; heinious; atrocious;
        infamous; impious. see iniquitous.
        1913 webster -- nefa"riously, adv. --
        nefa"riousness, n.
        1913 webster
see also:
no fate iniquitous nefa"riously nefa"riousness 

[2] : WordNet (r) 2.0

nefariousness
     n : the quality of being wicked syn: wickedness, vileness
see also:
wickedness vileness 

Nefariousness >> N Words
Nefariousness, definition of term: Nefariousness
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