The state or characteristic of being nefarious.(noun)
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Use "nefariousness" in a sentence
"But it does express my irritation with the way some liberals - and only some - assume a kind of nefariousness among those who have actually made a material success of their lives, and see no real loss in expropriating their moolah."
"They'd give me a mouthful, no doubt, something about needing to stay clear of this nexus of national nefariousness."
"I'm guessing I'd get a mouthful, something about needing to stay clear of this nexus of national nefariousness."