#circle  ellipse in which the two axes are of equal length; a plane curve generated by one point moving at a constant distance from a fixed point; "he calculated the circumference of the circle"
  supertype:  ellipse__oval  a closed plane curve resulting from the intersection of a circular cone and a plane cutting completely through it; "the sums of the distances from the foci to any point on an ellipse is constant"
  part:  arc
  subtype:  circle_of_curvature__osculating_circle  the circle that touches a curve (on the concave side) and whose radius is the radius of curvature
  subtype:  equator.circle  a circle dividing a sphere or other surface into two usually equal and symmetrical parts
  subtype:  epicycle  a circle that rolls around (inside or outside) another circle; generates an epicycloid or hypocycloid

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