in-joke vs prank

in-joke

noun
  • Synonym of inside joke (“a joke that is understood or meant to be understood only by certain people who are aware of the details”) 

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 in-joke and prank occurred in a corpus of books? (source: Google Ngram Viewer )