derogative vs dysphemism

derogative

noun
  • A derogatory word or word-form. 

adj
  • Disparaging; tending or intending to be belittling. 

  • Of or pertaining to derogation; that derogates 

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 derogative and dysphemism occurred in a corpus of books? (source: Google Ngram Viewer )