Overpronation is a commonly used and commonly abused term. It has become somewhat meaningless these days due to this wide spread use and abuse.
For a better understanding of overpronation, see
Overpronation in Runners | Overpronate | Overpronation | Overpronation | Overpronation: Accurate or Parachronistic terminology? | My Advice if you Overpronate | Overpronation
