place under suspicion or cast doubt upon; "sully someone's reputation"
make dirty or spotty, as by exposure to air; also used metaphorically; "The silver was tarnished by the long exposure to the air" "Her reputation was sullied after the affair with a married man"
charge falsely or with malicious intent; attack the good name and reputation of someone; "The journalists have defamed me!" "The article in the paper sullied my reputation"