Definitions
American Heritage® Dictionary of the English Language, Fourth Edition
- v. To attack as false or questionable; challenge in argument: impugn a political opponent's record.
Century Dictionary and Cyclopedia
- To attack by words or arguments; contradict; assail; call in question; gainsay.
Wiktionary
- v. transitive, obsolete To assault, attack.
- v. transitive To verbally assault, especially to argue against an opinion, motive, or action; to question the truth or validity of.
GNU Webster's 1913
- v. To attack by words or arguments; to contradict; to assail; to call in question; to make insinuations against; to gainsay; to oppose.
WordNet 3.0
- v. attack as false or wrong
Etymologies
- From Latin impugnō, from im- + pugnō ("fight"), from pugnus ("fist") (as in English pugilism ("fighting with fists, boxing")), from Proto-Indo-European roots. (Wiktionary)
- Middle English impugnen, from Old French impugner, from Latin impugnāre : in-, against; see in-2 + pugnāre, to fight; see peuk- in Indo-European roots. (American Heritage® Dictionary of the English Language, Fourth Edition)
Examples
“Wunderman said he didn't want to "impugn" the motives of officials in those cities, acknowledging they were serving the needs of their constituents.”
Jacksonville Business News - Local Jacksonville News | Jacksonville Business Journal
“The narrator doesn't impugn the behavior of man who fired his father for falling asleep on the job.”
The Huffington Post: Richard B. Woodward: We The Animals: Novel Of The Year?
“I don't think it's useful to impugn her motives; I think it's more useful to address her argument.”
GUEST POST: Jennifer Brissett Weighs in on the Writer Pay Rate Flap
“In a world in which God brought only good things, what would not impugn His goodness?”
“Meanwhile you make completely unsupported claims all over the place, and yet impugn my intellectual honesty.”
“If you are going to impugn the character of respected scientists, then we need some evidence other than a bald assertion.”
Matthew Yglesias » January Was the Warmest Temperature in World History
“While he notes that there are "patriotic reasons for strongly opposing higher tax rates," it is quite obvious that wealthy conservatives like Mr. Moore have compelling personal reasons for opposing them, too, and hence perfectly understandable why they might want to counter the perception that they are merely selfish and greedy by trying to impugn the character of those who disagree with them rather than focusing on the substance of our position.”
The Huffington Post: Eric Schoenberg: The Hypocritical Oath?
“Then again - not to impugn you, Leigh, or any of the readers/commenters - there is a degree to which our own cynicism determines whether we view a particular emotional expression as contrived or not.”
“Democrats in Texas are trying to stir things up by using half quotes to impugn his character, Sullivan said.”
The Huffington Post: Ron Paul, In 1996, 'Did Not Deny' Controversial Statement In Newsletter
Lists
These user-created lists contain the word ‘impugn’.
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Iaan
dirigisme, dystopia, cacotopia, ex ante, veritable, indefatigable, curmudgeon, desultory, antediluvian, transmogrify, pendent, elongate and 269 more...
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GRE 2014
abate, abdicate, abase, aberrant, abeyance, abhor, abjure, abortive, abound, abrasive, abreast, abridge and 1577 more...
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Naresh_Gre2
convoke, cosset, coterie, declaim, distaff, doff, dovetail, droll, dyspeptic, egress, ersatz, euphemism and 108 more...
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phrontistery - i
from phrontistery.info
iamb, ianthine, ibidem, iceblink, ichneumous, ichnite, ichnogram, ichnography, ictus, idolum, idoneous, ilke and 510 more...
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Previous GRE
churlish, martinet, polyglot, aplomb, dissembler, hack, dissimilitude, whit, histrionics, prevarication, pithy, aphorism and 16 more...
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man gre
abase, abeyance, abreast, abscission, abscond, abyss, accede, accretion, acerbic, acidulous, acumen, adulterate and 483 more...
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GRE Practice
coruscate, preternatural, preclude, retrench, perfidy, sophistry, sedulous, martinet, churlish, dissembler, prevarication, impugn and 38 more...
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big book gre
abase, abbess, abbey, abbot, abdicate, abdomen, abdominal, abduction, abed, aberration, abet, abeyance and 6691 more...
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gre2
aberrant, aberration, aboveboard, abrasive, abstemious, acme, admonish, affable, affluent, alacrity, allegory, alleviate and 1901 more...
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Citicize/Criticism
belittle, berate, calumny, castigate, decry, defamation, disparage, excoriate, gainsay, harangue, impugn, inveigh and 9 more...
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challenge
to deny or negate
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GRE Reference
A list of words unfamiliar to me that I have repeatedly encountered in GRE question sets.
parochial, clique, salacious, aegis, ostracize, conceited, sacrilegious, inane, serendipity, gourmand, polemic, tenuous and 138 more...
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Need to Know!
elicit, educe, refute, cogency, churlish, martinet, veritable, polyglot, dissemble, histrionics, prevarication, verbiage and 166 more...
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newGRE
mostly from magoosh
imbue, verge on, nonchalant, deliberate, timorous, futile, provisional, dissect, checked, tinged, alluring, visionary and 1046 more...
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SAT PSAT ALPHABETICAL I
iconoclast, idiosyncrasy, ignoble, ignominious, illicit, illusory, illustrious, imbibe, imbue, immaculate, immaterial, immolate and 155 more...
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My Revised GRE Preparation List
Words from the new GRE : This list consists mostly of words from the book Magoosh-GRE-vocab-ebook, which is one of the best vocab materials available, especially if you have started preparing one ...
alacrity, prosaic, veracity, paucity, contrite, trite, maintain, laconic, pugnacious, disparate, egregious, innocuous and 533 more...
Tweets
Looking for tweets for impugn.

Dan337
It appears (from, e.g., almost every sentence cited on the first page of usage examples for “impune”*) that almost every person who writes the word “impune” in English intends the word “impugn”.* The only two exceptions use the word in the Latin† motto “Nemo me impune lacessit” (or a fragment thereof).
† That is to say the language of the motto is Latin; it’s the motto of the Order of the Thistle, a chivalric order associated with Scotland. Jan 6, 2011
sonofgroucho Great word: not used nearly often enough. I feel as if it should be connected with impunity, but it doesn't seem to be. Nov 11, 2007