A toilet prank, whereby someone defecates in the refill tank (water closet), causing each additional flush to deliver brown, poopy water into the bowl.

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 act of sneaking into a bathroom, quietly lifting the lid off of the toilet tank, taking a deuce in the tank and then replacing the lid. this causes the toilet water in the bowl to be polluted after each flush. this is usually done at a party or too someone that you despise.

When attending a persons home of who you dislike, take a shit in the toliet tank instead of the bowl. This is by far going out of the park and into the upperdeck where it will not be known until long after you depart their house.

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.

The act of shitting into the tank (or upper portion) of a toilet. Done as a prank, it results in at least four foul flushes (also known as a "3-F qualifier") afterwards.

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.