incongruity vs nonhomogeneity

incongruity

noun
  • The state of being incongruous, or lacking congruence. 

  • A thing that is incongruous. 

  • An instance or point of disagreement 

nonhomogeneity

noun
  • Absence of homogeneity. 

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