ligature vs wall knot

ligature

noun
  • A cord or similar thing used to tie something; especially the thread used in surgery to close a vessel or duct. 

  • A piece used to hold a reed to the mouthpiece on woodwind instruments. 

  • The state of being bound or stiffened; stiffness. 

  • A character that visually combines multiple letters, such as æ, œ, ß or ij; also logotype. Sometimes called a typographic ligature. 

  • A group of notes played as a phrase, or the curved line that indicates such a phrase. 

  • The act of tying or binding something. 

  • Impotence caused by magic or charms. 

  • A curve or line connecting notes; a slur. 

  • A thread or wire used to remove tumours, etc. 

verb
  • To ligate; to tie. 

wall knot

noun
  • A knot made by unlaying the strands of a rope, and making a bight with the first strand, then passing the second over the end of the first, and the third over the end of the second and through the bight of the first. 

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