headstall vs rein

headstall

noun
  • The part of a bridle that fits over a horse's head and supports other elements. 

rein

noun
  • A strap or rope attached to a bridle or bit, used to control a horse, animal or young child. 

  • The inward impulses; the affections and passions, formerly supposed to be located in the area of the kidneys. 

  • An instrument or means of curbing, restraining, or governing. 

verb
  • To restrain; to control; to check. 

  • To obey directions given with the reins. 

  • To direct or stop a horse by using reins. 

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