A drug dealer who deals largely in hallucinogens. Will usually, but not always, reject the idea of selling other types of drugs, such as cocaine or opiates. Many "acid dealers" are in the business to "turn" others "on," rather than make a large profit, and as such, are often less dangerous than your typical dealer.
"I went to my acid dealer the other day to pick up a ten strip. We smoked out and listened to some music. It was mad chill."