frolic vs joke

frolic

verb
  • To make merry; to have fun; to romp; to behave playfully and uninhibitedly. 

noun
  • Gaiety; merriment. 

  • A playful antic. 

joke

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

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

noun
  • An amusing story. 

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

  • 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. 

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