From Longman Dictionary of Contemporary Englishsullysul‧ly /ˈsʌli/ verb (sullied, sullying, sullies) [transitive] formal or literary SPOILto spoil or reduce the value of something that was perfect a scandal that sullied his reputation→ See Verb table
Examples from the Corpus
sully• They stood for progress, a notion already being sullied by contempt for the military-industrial complex.• Is it too pure to be sullied by the messiness of domestic life?• And when his human dignity was gone, his innocence sullied, he felt something sharp plunge into his chest.• And I must take care not to sully it, is that it?• Instead, the general manager has sullied the whole outfit.• Oil spills have sullied thousands of acres.Origin sully (1500-1600) Probably from Old French soiller; → SOIL2