joke vs tragedy

joke

noun
  • The root cause or main issue, especially an unexpected one 

  • An amusing story. 

  • A laughably worthless thing or person; a sham. 

  • Something that is far easier or far less challenging than expected. 

  • Something said or done for amusement, not in seriousness. 

verb
  • To do or say something for amusement rather than seriously. 

  • To dupe in a friendly manner for amusement; to mess with, play with. 

tragedy

noun
  • A disastrous event, especially one involving great loss of life or injury. 

  • A drama or similar work, in which the main character is brought to ruin or otherwise suffers the extreme consequences of some tragic flaw or weakness of character. 

  • The genre of such works, and the art of producing them. 

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