Stigma, brand, blot, stain can denote a mark of shame left on a name, reputation, or character.
Stigma , though often implying dishonor or public shame, usually applies to a mark or a charge or judgment that is fastened upon a person or thing or is attached to it so as to discredit it and cause it to be generally disapproved or condemned.
Brand carries stronger implications of disgrace and infamy than stigma ; it often suggests impossibility of removal, permanent social ostracism, and public condemnation.
Blot and stain imply a blemish that diminishes the honor of a name or a reputation or that sullies one’s reputation for purity or virtue but does not bring either name or reputation into utter disrepute.