A smear campaign, also referred to as a smear tactic or simply a smear, is an effort to damage or call into question someone's reputation, by propounding negative propaganda. It makes use of discrediting tactics.
It can be applied to individuals or groups. Common targets are public officials, politicians, political candidates, activists and ex-spouses. The term also applies in other contexts such as the workplace.
The term smear campaign became popular around 1936.