#roundness__roundnes  the property possessed by a line or surface that is curved and not angular
  exclusion:  angularity
  supertype:  contour__shape__form__configuration  any spatial attribute (especially as defined by outline); "he could barely make out their shapes through the smoke"
  subtype:  sphericity__sphericalness__sphericalnes__globularness__rotundity  the roundness of a 3-dimensional object
  subtype:  cylindricality__cylindricalness  the roundness of a 3-dimensional cylinder
  subtype:  circularity__disk_shape  the roundness of a 2-dimensional figure
     subtype:  concentricity  the quality of having the same center (as circles inside one another)
     subtype:  eccentricity.circularity  a circularity that has a different center or deviates from a circular path

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