When a man sticks his head up another man's ass and they pretend to be a centaur.
The man on top can shoot a bow and arrow, but it's optional.
Centaurs are beautiful creatures, but rusty horses are more majestic.

The other day I went to the rodeo and rusty horsed in the stables with my partner, luckily he didn't bring his bow and arrow this time.
by PJBJ January 24, 2017
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One runs there finger around the butthole of a horse collecting all the excess poop then slathering the feces on two buns creating the best culinary masterpiece, then insert your penis in this gooy mess until there's nothing left.
The other night I was with the boys and I had myself a good old fashion rusty horse burger.
by BiggestRich March 1, 2017
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