clopper

One who clops; a horse.

Mr Binks over there is his front legs, and works his head, the horse's head, I mean. You should see old Clopper when he performs! My, there isn't a horse like him in the world.

His slow-paced horse, a clopper and carrier of bells, filled the empty awakening.

One who engages in clopping.

Considering that a significant percentage of bronies are closeted, and taking into account the stigma attached to such practices, it is fair to assume that the real "clopper" population is likely far larger.

One clopper recently gained quite a bit of notoriety on the Internet by revealing just how far his obsession with the show had gone.