insipidity vs mordancy

insipidity

noun
  • Something that is insipid; an insipid utterance, sight, object, etc. 

  • The condition of being insipid; insipidness. 

mordancy

noun
  • The state or quality of being mordant. 

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