impropriety vs propriety

impropriety

noun
  • The condition of being improper. 

  • An improper act. 

  • Improper language. 

propriety

noun
  • The fact of possessing something; ownership. 

  • Suitability, fitness; the quality of being appropriate. 

  • Correctness in behaviour and morals; good manners, seemliness. 

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