The act of defecating. The issuance of fecal material from the colon, via the shit chute, into (or upon) something either utilitarian or symbolic.
"Hey in there - what's taking so long? I hope for your sake you're not pushing mud! We're out of a-wipe and crapper spray!"
by Commode Mouth September 17, 2006
A basic bowel movement. Usually reserved for high-volume output. Especially after lunch when you feel like it will take a great feat of strength to go poop.
I was just in the 3rd stall pushing mud, so wait about 30 to 45 minutes before you go in there.
by Neil Larocca June 06, 2005