boycock vs joystick

boycock

noun
  • The penis of a young man. 

joystick

noun
  • A penis. 

  • A mechanical device consisting of a handgrip mounted on a base or pedestal and typically having one or more buttons, used to control an aircraft, computer, or other equipment. 

verb
  • To manoeuvre by means of a joystick. 

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