dysphemism vs euphemism

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. 

euphemism

noun
  • The use of a word or phrase to replace another with one that is considered less offensive, blunt or vulgar than the word or phrase which it replaces. 

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

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