Upperdecking

Removing the lid of the back of someone's toilet and shitting in the clean water. Results in shit running into the boil with every flush

That bitch pissed me off, so I upperdecked her shitter

by Dan April 5, 2004

Upperdecking

This one takes practice. This maneuver requires a toilet with a tank above it, like the ones in most homes. Instead of crapping in the bowl, you shit in the tank. Now don't flush. When the following victim flushes, the rancid waste fills the bowl. If you play your cards right, it may ferment. Great prank for those lame partys.

"I gave that toilet a nice upperdecking, Just wait till she comes outta there"

by CharlesVA August 5, 2006

Upperdecking

Using the restroom, going number one or two in the water tank of a fellow man's toilet. when he flushes the pee or shit flows out.

The other night we were upperdecking, it was funny as shit.

by douchebagness May 16, 2007

underdecking

conspiring against an authority figure to take synchronized shits underneath said authority figure's deck. Usually performed in groups of two to five people. In extreme cases, shit burritos are fashioned with paper towels and left to be found.

Oh, no. Have you seen the kids? I hope their not underdecking us again!

by underdecked July 2, 2009

upper decking

The process of taking a shit in the tank of a toilet instead of the bowl so when the next person flushes, all the shit goes into the bowl

Taking a shit in the tank instead of the toliet is upper decking.

by Jay December 26, 2003

Upper Decking

giving John Barrowman a blowjob on a transatlantic flight

"In the middle of the night ... on a 747 on the upper deck" (hence the term "upper decking")

by qwapos September 7, 2012

Upper Decking

Deficating in the tank of someone's toilet, rather than the bowl. Often employed in malicious context.

Suzy could not figure out why her toiled would flush only brown water. Little did she know that Johnny had upper decked that bitch the previous night.

by Korthos July 27, 2004