ballbag vs coin purse

ballbag

noun
  • The scrotum. 

  • A thoughtless and ignorant individual. 

coin purse

noun
  • Testicles. 

  • A small bag or pouch designed for carrying money, particularly coins. 

  • a type of theatrical performance undergarment used to hide male genitalia, by stuffing it into a pouch with a drawstring, to simulate being nude 

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