Acronym for: (Wet Paper Bag) A term for having the explosive shits really bad. Just imagine if your carrying a paper bag full of stuff and the bottom gets wet and tears open and everything falls out. That's what happens to your ass. Synonym for explosive diarrhea.
Oh man I have WPB really bad, if you don't get me to the bathroom pronto, your car is going to get it.
by Sima July 05, 2005