addition vs appurtenance

addition

noun
  • The act of adding anything. 

  • The arithmetic operation of adding. 

  • A dot at the right side of a note as an indication that its sound is to be lengthened one half. 

  • Anything that is added. 

  • A title annexed to a person's name to identify him or her more precisely. 

  • Something added to a coat of arms, as a mark of honour. 

appurtenance

noun
  • That which appertains; an appendage to something else; an addition. 

  • Equipment used for some specific task; gear. 

  • A subordinate interest in land which benefits a principal estate, which cannot be detached from or held separately to that estate; an appurtenant interest. 

  • A modifier that is appended or prepended to another word to coin a new word that expresses belonging. 

  • The state or quality of being an appurtenance. 

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