The act of filling up ones anus with a fluid, typically water from a hose. Then releasing the water like a geyser upon an unsuspecting victims head.
I stuffed cheese curds into my ass hole and then with a medically issued super soaker and careful precision I received an injection of One love Kombucha into my anus. Then during an ugly sweater party, many months later, I pulled down my pants spread my butt cheeks and with the the force of old faithful I shot my cheese curd laced kombucha turd Butt Geyser all over the head of one special party goer ronnathan blox.
by Mr. Richard-Finger Tongue September 17, 2015
the splash that enters your butt due to your sphincter not being fully closed, once you drop a hefty turd
by Vladboy11 November 20, 2011
The insertion of one's penis into an anus (male or female), followed by the expulsion of urine, rather than ejaculate, into the anal cavity.
She's going to know that she got a Yellowstone National Butt Geyser, once she realizes I had asparagus for dinner.
by bonerchugger6969 December 06, 2010