hash mark vs quadrilateral

hash mark

noun
  • One of the parallel lines on either side of the face-off circles. 

  • A service stripe, as on an enlistee’s uniform sleeve. 

  • An inbounds line. 

  • The hash or pound sign (#). 

quadrilateral

noun
  • A polygon with four sides. 

  • An area defended by four fortresses supporting each other. 

adj
  • Having four sides. 

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