A turd muffin is the act of being, stupid, commonly reffered to as dumb, retarded.
Dude, stop being a turd muffin.
by Alec "Baldwin" November 28, 2004
a strange word for when you just cant seem to think of anything else to say. Comes from the words turd and muffin.
"Geez man your such an ass" "Oh yea well um... um... your a turdmuffin!"
by Fish December 15, 2004