The University of Mississippi (also known as "Ole Miss") was the first university in the state of Mississippi, United States.
During the mid-2240s, Leonard McCoy attended Ole Miss prior to entering the medical profession. While there he met a Trill, named Emony Dax, who was on Earth judging a gymnastics competition at the university. (DS9: "Trials and Tribble-ations")
The Star Trek Encyclopedia speculates that Emony and McCoy met around 2245, this based on the fact that McCoy appears to have not yet entered medical school when they knew each other.
The gymnastics competition at the University of Mississippi is featured in The Lives of Dax short story "Old Souls".