inexistence vs nonentity

inexistence

noun
  • The state of not being, not existing, or not being perceptible. 

  • The state of existing in something 

  • That which exists within; a constituent. 

nonentity

noun
  • the state of not existing; nonexistence 

  • an unimportant or insignificant person 

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