#friction__rubbing  the resistance encountered when one body is moved in contact with another
  supertype:  #resistance.mechanical_phenomenon  any mechanical force that tends to retard or oppose motion
  subtype:  #abrasion__grinding__attrition__detrition  the wearing down of rock particles by friction due to water or wind or ice
  subtype:  #adhesive_friction__grip__traction  the friction between a body and the surface on which it moves (as between an automobile tire and the road)

No statement uses or specializes #friction; click here to add one.