incongruity vs unintelligibility

incongruity

noun
  • A thing that is incongruous. 

  • The state of being incongruous, or lacking congruence. 

  • An instance or point of disagreement 

unintelligibility

noun
  • Something that is unintelligible. 

  • The quality or condition of being unintelligible. 

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