Mountain Doo 

Taking a really huge dump to learn that it all stacked on each other, creating a mountainous form.

I totally just took a mountain doo in your bathroom.

Mountain Doo by Alteffore808 August 2, 2009

Mountain doo-doo 

When you drink a large amount of Mountain Dew, and subsequently have diarrhea. Preferably, on a mountain.

"The deer were totally checking out my mountain doo-doo."

Mountain doo-doo by jimmyjimjamboree April 19, 2010

mountain dookie 

The nasty-ass shit you take after chugging four cans of mountain dew in the morning. Also known as mountain deuce.

Yo man where's Jimmy? I can't find him anywhere. Class starts in 10 minutes.

I think he's on the can dropping a mountain dookie.

mountain dookie by Pdoody July 13, 2012