when your weiner gets all covered in poop. most likely from banging a drunk highschool girl in the ass.
dude, the other day i had a party at my house and we were drinkin a keg of Busch Light, then we all got real horny and decided it would be a good idea to go bang all the girls in the ass. Midway through this ass bangin my mom came home and caught me. I pulled my weiner out of the girls ass and said "awwwww mom, i got poopdick."
An insult used to describe a person who is being, or is in general, an asshole. It is used when calling said person a dick does not completely suit the shitiness of their actions.
Sam-"Hey look you dyed your hair blonde. Haha you look like Hitler."
Dana-"Stop being such a poopdick, Hitler doesn't even have blonde hair."