"Impugn" is a transitive verb meaning to cast doubt upon or to challenge or attack as false. The following sentences provide examples of its use: Don't you dare try to impugn my credentials. The...
Teens often impugn the restrictions put on them, like curfews and chores.
I would be deeply offended if you were to impugn my honesty.
I impugned him by providing evidence against him with witnesses
To impugn is to challenge, oppose or attack as being false. Usage: I impugn you. 'I impugn your belief that the world is flat'