tr.v. im·pugned, im·pugn·ing, im·pugns
To attack as false or questionable; challenge in argument: impugn a political opponent's record.
[Middle English impugnen, from Old French impugner, from Latin impugnāre : in-, against; see IN-2 + pugnāre, to fight; see peuk- in the Appendix of Indo-European roots.]
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