#concave_polygon__concavepolygon  a polygon such that there is a straight line that cuts it in four or more points
  exclusion:  #convex_polygon
  supertype:  #polygon__polygonal_shape__polygonalshape  a closed plane figure bounded by straight sides
  subtype:  #reentrant_polygon__reentrantpolygon__reentering_polygon  a polygon with one or more reentrant angles

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