oat-burner

noun2

1. •
   A horse.

   • He's not just your basic oat-burner who runs because he's taught to. — 2008
2. •
   A film, radio or television show, or theatrical production set in the Old West; horse opera.

   • Here are the two lead sentences in the liner notes for a recently released western, an oat-burner just out on video called Covenant Rider. — 1996