One who impugns; one who opposes or contradicts.(noun)
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Use "impugner" in a sentence
"Under that is the hater, the impugner of motives … this is the contemptuous, contemptible layer that stimulated him to engage ‘plumbers’ to plug news leaks and to trample civil liberties in what he saw as a higher cause…."
"I thereby impugne the false impugner who calls himself “Your Conscious.”"
"At the conclusion of peace the man went back to politics, a trade for which his temperament was better fitted; and it was he who was chosen as the chief impugner of the conduct and honour of Andrew Johnson!"