The definition of nefarious is someone who is known for being very wicked.(adjective)
An example of nefarious is Adolf Hitler.
See nefarious in Webster's New World College Dictionary
Origin: L nefarius < nefas, crime, sin < ne-, not + fas, (divine) law, lawful
See nefarious in American Heritage Dictionary 4
Origin: Latin nefārius
Origin: , from nefās, crime, transgression
Origin: : ne-, not; see ne in Indo-European roots
Origin: + fās, divine law; see dhē- in Indo-European roots.
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