calumny vs dysphemism

calumny

noun
  • Falsifications or misrepresentations intended to disparage or discredit another. 

  • A false accusation or charge brought to tarnish another's reputation or standing. 

verb
  • To make false accusations or levy false charges against a person with the intent to tarnish that person's reputation or standing; to calumniate. 

dysphemism

noun
  • The use of a word or phrase carrying negative connotations or imagery (especially one that is derogatory, offensive or vulgar) to replace a (more) neutral original. 

  • A word or phrase that is used to replace another in this way. 

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