inexistence vs mu

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. 

mu

noun
  • Nothingness; nonexistence; the illusory nature of reality. 

  • The 12th letter of the Modern Greek alphabet. 

  • A unit of surface area, currently equivalent two-thirds of a decare (about 666 meters squared). 

intj
  • Neither yes nor no. 

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