Morrison made the gesture while sitting on the bench late in overtime during Charlotte's 111-103 win over the Heat on Sunday. Morrison did not play in the game because of a sprained knee, the first game he missed this season.
Morrison said he was being heckled throughout the game.
"I've got to learn to take it, I guess, but I think the guy went over the edge a little bit, calling me 'white trash' over and over again," said Morrison, who also sat out Tuesday's game against Miami. "I reacted naturally and I made a mistake. I hurt the organization and the team. I'm sorry about it and it will never happen again."
