Third-person singular simple present indicative form of impugn.(verb)
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Use "impugns" in a sentence
"Naturally, I don't want anything that impugns the integrity of the industry."
"Lungren interrupted with a point of order, asking that Blumenauer's words be "taken down" -- a form of mild censure for "unparliamentary" language that impugns another member's motives."
"Nothing in the signs impugns the reputation of the Beach Club or insinuates that it is guilty of criminal conduct."