oversum vs superfluity

oversum

noun
  • A whole that is more than the sum of its parts; superaddition. 

verb
  • To add up incorrectly, arriving at a total that is too large. 

superfluity

noun
  • The quality or state of being superfluous; overflowingness. 

  • Something superfluous, as a luxury. 

  • Collective noun for a group of nuns. 

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