- nefarious (adj.)
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- 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," from PIE root *bha- (2) "to speak, tell, say" (see fame (n.)). Related: Nefariously.