Definition: The shoe sole between the outer sole (which contacts the ground) and the shoe upper. It is made of a variety of materials to give the shoe various characteristics of cushioning, support, and flexibility. Different colors of materials show the different densities - usually the denser and more supportive polyurethane is in gray, with the lighter and cushier EVA in white. The more gray, the more support. The more white, the more flexible and cushioned.
Pronunciation: mid sole (noun)