The sexual act in which, after a thorough reaming of a ladies ass, you flip her upside down and poop into her gaping butt cavity.
Last night I gave that skank whore the old Mongolian Chimney sweep and got crap all over the hotel.
by El Kroppo July 17, 2008
A sexual act performed following anal intercourse, where the person who was being penetrated does a head-stand exposing his/her gaping anus and the penetrator sits atop the penetratee and defecates into their rectum.
The Mongolian Chimneysweep requires some degree of flexibility.
by The Grand MasterSmeat (courtesy of Scott) August 30, 2006