appendix vs ell

appendix

noun
  • The vermiform appendix. 

  • A text added to the end of a book or an article, containing additional information. 

  • Any process, prolongation, or projection. 

ell

noun
  • Something that is L-shaped. 

  • The name of the Latin-script letter L. (more commonly el) 

  • A measure of length. An English ell was 1¼ yards (45 inches or 114 cm), a Scottish ell was about 37 inches (94 cm), a Flemish ell was ¾ yard (27 inches or 69 cm), while certain European ells were less than 50 cm. 

  • An extension usually at right angles to one end of a building. 

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