"Impugnation" refers to the act of challenging or questioning something. Synonyms for this word include: questioning, challenging, disputing, contesting, objecting, refuting, opposing, contradicting, denying, discrediting, and invalidating. These synonyms all share the meaning of casting doubt on the validity or truthfulness of something. Instead of using repetitive language, these synonyms can help add variety to your writing and make it more engaging. They can be particularly useful when writing persuasive or argumentative essays, as they provide options for expressing disagreement and presenting counterarguments. Overall, using synonyms for "impugnation" can enhance the clarity and impact of your writing.