swivel vs ulna

swivel

noun
  • A piece, such as a ring or hook, attached to another piece by a pin, in such a manner as to permit rotation about the pin as an axis. 

  • A small piece of ordnance, turning on a point or swivel; called also swivel gun. 

  • Strength of mind or character that enables one to overcome adversity; confidence; force of will. 

  • The act of swivelling. 

  • A rotating of the hips. 

  • A small, usually ball- or barrel-shaped device used in angling to connect sections of fishing lines, consisting of two rings linked via a thrust bearing pivot joint. 

verb
  • To swing or turn, as on a pin or pivot. 

ulna

noun
  • The bone of the forearm that extends from the elbow to the wrist on the side opposite to the thumb, corresponding to the fibula of the hind limb. Also, the corresponding bone in the forelimb of any vertebrate. 

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