horse docking 

The act of placing one's head inside the foreskin of a horses penis. Similar to regular docking.

Mom didn't come back from the barn last night because the stallions large foreskin was the perfect size for her head. She was busy horse docking.

horse docking by Dr Martin Dingles November 12, 2012

horsecocking 

The act to telling a girl to "saddle up" as a man shoves his all mighty penis vigorously into a woman's asshole and screams "YeeHaw! Ride it little pony!"

The man enjoyed a night out "horsecocking" a lot of women.

horsecocking by Kongjong123 July 23, 2015