impugn

UK: /ɪmˈpjuːn/ US: /ɪmˈpjun/ ,(im pyo̅o̅n′)

WordReference Random House Learner's Dictionary of American English © 2025

im•pugn /ɪmˈpyun/   v. [~ + object]

1. to cast doubt upon:
   The lawyer impugned the witness's story.

im•pugn•er, n. [countable] See -pugn-.

WordReference Random House Unabridged Dictionary of American English © 2025

im•pugn  (im pyo̅o̅n′), v.t. 

1. to challenge as false (another's statements, motives, etc.);
   cast doubt upon.
2. [Archaic.] to assail (a person) by words or arguments;
   vilify.
3. [Obs.] to attack (a person) physically.

• Latin impugnāre to attack, equivalent. to im- im-¹ + pugnāre to fight, derivative of pugnus fist; see pugnacious
• Middle French impugner
• Middle English impugnen 1325–75

im•pugn′a•ble, adj. 
im•pugn′a•bil′i•ty, n. 
im•pugn′er, n. 
im•pugn′ment, n. 
Synonyms

• 1. attack, asperse, malign, criticize, censure.

Collins Concise English Dictionary © HarperCollins Publishers::

impugn / ɪmˈpjuːn/ verb

1. (transitive) to challenge or attack as false; assail; criticize

Etymology: 14th Century: from Old French impugner, from Latin impugnāre to fight against, attack, from im- + pugnāre to fight

imˈpugnable adjective

impugnation / ˌɪmpʌɡˈneɪʃən/, imˈpugnment noun

imˈpugner noun