1. Literally expelling urine from one's ass after having the urine injected into the anus during the act of a pistol star.
2. A specific type of diarrhea, wherein the contents of one's ass is expelled in a liquified, piss-like manner.
Paul was buttpissing all night after the girls all gave him a good pistol star.
Grant had to seriously buttpiss the morning after Joey gave him a pistol star for his birthday.
The so-annoying loosening of your belt that ends up interfering the piss flow and thereby giving it a whole new, random and really "wet-panting" result
A: Dude, WtF happened in there? look at ur pants...
B: Remember that beltJill gave me for my bd last week.
A: yeah... so?.
B: Beltpiss.
A: fuuuuuuuuuuuuuuuuu... hold my belt i need to go now.
1. (noun) A combination of Mountain Dew Voltage, Sprite, Red Bull, Raspberry Sherbet, and vodka
2. (verb) (-ed) To become drunk off of Bullpiss
3. (adj) (-ed) To be angry at someone while drunk
"Dude we are making some bullpiss tonight!"
"We are so bullpissed right now."
"I was so bullpissed at her when she kept asking me what was going on while we were watching Stepbrothers"
Diarrhea, or liquid shit that comes out of your ass. Sometimes occurs when eating Mexican food, eggs, or drinking too much whole milk. Akin to shitting a lot of Yoo-Hoo.
Holy fuckin shit dude, your mom's eggcasserole gave me some SERIOUS buttpiss!!