v. The leaving of fecal matter in the tank of ones toilet, turning the water brown. Primarily done as revenge or a drunken practical joke, but sometimes in an emergency when the bowl is clogged.
n. The shit that is left in tank during such an act.
I got so wasted last night I upperdecked Sean, his bathroom is going to stink for weeks.
By Gertrudis
Upper Decking
The process of taking a shitin the tank of a toilet instead of the bowl so when the next person flushes, all the shit goes into the bowl
Where you go to someone's house, shit in the tank part of the toilet. the shit in there starts rotting, and starts smelling up the bathroom, and people don't know where the smell is coming from because they never look in the tank part of the toilet.
That guy Jimmy threw a party last week. He tried to kick me out, so I upper decked his ass. Then I wiped some shit in his bedspread. I hate that jerk, but he straight got shitowned!