#bore_bit__borer__rock_drill__stone_drill  a drill for penetrating rock
  supertype:  #drill  a tool with a sharp point and cutting edges for making holes in hard materials (usually rotating rapidly or by repeated blows)
  subtype:  #cross_bit__crossbit  a rock drill having cruciform cutting edges; used in mining
  subtype:  #star_drill  a steel rock drill with a star-shaped point that is used for making holes in stones or masonry; it is operated by hitting the end with a hammer while rotating it between blows
  subtype:  #straight_flute__straight-fluted_drill  a rock drill with straight flutes

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