frivolity vs prank

frivolity

noun
  • frivolous act 

  • state of being frivolous 

prank

noun
  • A practical joke or mischievous trick. 

verb
  • To make an ostentatious show. 

  • To perform a practical joke on; to trick. 

  • To call someone's phone and promptly hang up 

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