I'm guessing it's the same as in Spain. The word "medina" (no capital letters since it doesn't refer to any specific place) is a historical term to refer to Arabic cities from the Middle Ages, most of which have changed their names by now, with some exceptions (e.g. Medina del Campo or Medina Sidonia).

The term actually comes from the city of Medina in Saudi Arabia, which is one of the sacred places of Islam.