insincerity vs prevarication

insincerity

noun
  • Property of being insincere, lacking sincerity or truthfulness. 

prevarication

noun
  • Evasion of the truth. 

  • A secret abuse in the exercise of a public office. 

  • A false or deceitful seeming to undertake a thing for the purpose of defeating or destroying it. 

  • The collusion of an informer with the defendant, for the purpose of making a sham prosecution. 

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