pacemaker vs shepherd

pacemaker

noun
  • One who sets the pace in a race, to guide the others. 

  • A set of nerves which stimulate the heart to beat. 

  • A medical implement that is used to stimulate a heart to beat by simulating the action of the natural pacemaker. 

shepherd

noun
  • A male watcher/guardian/guider/leader 

  • A person who tends sheep, especially a grazing flock. 

  • Someone who watches over, looks after, or guides somebody. 

  • A swain; a rustic male lover. 

  • The pastor of a church; one who guides others in religion. 

  • A male sheep tender 

  • A German Shepherd. 

  • A male pastor 

verb
  • To obstruct an opponent from getting to the ball, either when a teammate has it or is going for it, or if the ball is about to bounce through the goal or out of bounds. 

  • To watch over; to guide. 

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