A horse that is trained to back up to a stump. The owner of said horse then proceeds to stand on the stump, and vigorously fornicates the horse.
Cowpoke - "Is that a stump broke horse?"
Rancher - "Yeah, I backed 'er up to a stump and fucked the shit out of 'er jes last night.
by Spizzum August 10, 2006
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