appurtenance vs supplementary part

appurtenance

noun
  • Equipment used for some specific task; gear. 

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

  • 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. 

supplementary part

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