The act of removing the upper lid to a home toilet. leaving an imense amount of defacation inside. the next customer will go and then flush your shit into the bowl, repeatedly.
while in ohio, the clarion hotel wouldnt give us a room because we werent 21, so ryan anson gave them an upper decker
by friend July 30, 2003
Get the upper decker mug.When you take a crap in the tank of someones toilet instead of the bowl. Most often done to a sworn enemy or to your best friend.
by Helvis September 16, 2003
Get the Upper Decker mug.The act of removing the lid off the back part of a toilet and pooping in it. Poop comes in the bowl over time after flushes. Usually done at big parties that have gone wrong.
The host of that party was so horrible that Andre couldn't resist pulling an upper decker before we left.
by Agenda July 31, 2005
Get the upper decker mug.When someone poops in the top part of a toilet, (the part that you have to take the top off) so when someone else goes to the bathroom and flushes the toilet instead of clean water coming in and filling the toilet, shit water comes in. This is done as a pratical joke, usually done at parties.
Guy 1:Hey I just did that Upper Decker in the toilet upstairs and Jennifer went in there.
Guy 2:Hahahah, what'd she do when she came out?
Guy 1:I don't know, she's still in there!
Guy 2:Hahahah, what'd she do when she came out?
Guy 1:I don't know, she's still in there!
by Kevinnnnnnnnnn December 26, 2009
Get the Upper Decker mug.the act of deficating in the water tank of someones restroom, so when they flush, out comes muddy madness
by darby krow February 13, 2010
Get the upper decker mug.by Goldgoatturd February 20, 2009
Get the Upper Decker mug.Valerie was so drunk she did an upper decker in her friends toilet at the party, and everyone smelt it.
by valere March 13, 2008
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