shunter vs switcher

shunter

noun
  • A railway locomotive used for shunting; a switcher. 

  • A person who carries out shunting operations. 

  • One who shunts (carries on arbitrage between London and provincial stock exchanges). 

switcher

noun
  • A railway locomotive used for shunting; a shunter. 

  • A switchmode power supply. 

  • Synonym of vision mixer (“device for selecting between video sources”) 

  • One who or that which operates a switch. 

  • One who or that which switches, or changes to something else. 

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