defamation Play nounThe action of damaging the good reputation of someone; slander or libel. SYNONYMS abuseaspersionsbackbitingbad-mouthingcalumnycensurecharacter assassinationcontumelycriticismdefamation of characterdenigrationderogationdetractiondisparagementfalse reportinsultknockinglibelliemaledictionmalicious gossipmuckrakingmud-slingingobloquyopprobriumrumourscandalscandalmongeringslagging offslanderslursmearsmear campaigntittle-tattletraducementvilification