When you have take a crap so bad it starts commin' out before you make it to the toilet/water closet and you can feel the turd pushin' against your underwear.
Man I gotta shit so bad I'm already pokin' cotton.
|2.||Double ended underwear boat|
Ususally plural, since it requires a hard on and a turtle head at the same time. Also known as a Double ender.
He left in a real hurry after he said he was pushin cotton. I think he got excited too because when he stood up he had a double ended underwear boat goin on.