incurvature vs whorl

incurvature

noun
  • curvature; curving 

whorl

noun
  • Each circle, volution or equivalent in a pattern of concentric circles, ovals, arcs, or a spiral. 

  • A circle of three or more leaves, flowers, or other organs, about the same part or joint of a stem. 

  • A flywheel, a weight attached to a spindle. 

  • A volution, or turn, of the spire of a univalve shell. 

  • Any volution, as for example in the human ear or fingerprint. 

verb
  • To form a pattern of concentric circles. 

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