curvature vs kiss curl

curvature

noun
  • The shape of something curved. 

  • The extent to which a Riemannian manifold is intrinsically curved. 

  • The extent to which a subspace is curved within a metric space. 

kiss curl

noun
  • A spiral-shaped curl of hair upon the forehead. 

How often have the words curvature and kiss curl occurred in a corpus of books? (source: Google Ngram Viewer )