The definition of impugn is to question the truthfulness or validity of a statement.(verb)
An example of impugn is when you call someone out on what you believe to be a lie.
See impugn in Webster's New World College Dictionary
Origin: ME impugnen < OFr impugner < L impugnare < in-, on, against + pugnare, to fight: see pugnacious
See impugn in American Heritage Dictionary 4
transitive verb im·pugned, im·pugn·ing, im·pugns
Origin: Middle English impugnen
Origin: , from Old French impugner
Origin: , from Latin impugnāre
Origin: : in-, against; see in-2
Origin: + pugnāre, to fight; see peuk- in Indo-European roots.
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