impertinence vs obstinence

impertinence

noun
  • Insolence; impudence. 

  • Lack of pertinence; irrelevance. 

  • An instance of this; a moment of being impertinent. 

  • The fact or character of being out of place; inappropriateness. 

obstinence

noun
  • Synonym of obstinacy; Misspelling of obstinance. 

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