dysphemism vs substitute

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. 

substitute

verb
  • To remove (a player) from the field of play and bring on another in his place. 

  • To serve as a replacement (for someone or something). 

  • To use in place of something else, with the same function. 

  • To use X in place of Y. 

  • To use Y in place of X; to replace X with Y. 

noun
  • A player who is available to replace another if the need arises, and who may or may not actually do so. 

  • A replacement or stand-in for something that achieves a similar result or purpose. 

  • One who enlists for military service in the place of a conscript. 

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