trunnion vs whorl

trunnion

noun
  • A shaft, held by a bearing, at each end or side of a rotatable object. 

  • A similar rotational bearing comprising a rotating arc or ring sliding in the groove of a stationary arc, used in machinery to allow a workpiece to be moved relative to a fixed tool. 

  • A similar rotational bearing used in automotive suspensions. 

  • One of the short stubby bearings on either side of a cannon; a gudgeon. 

whorl

noun
  • A flywheel, a weight attached to a spindle. 

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

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

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

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

verb
  • To form a pattern of concentric circles. 

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