Best definition
watery ending
Adj.
A bowel movement beginning as a solid production, but turns violently into liquid just before finishing.

Man, after a hard night of drinking at that bachelor party in Vegas, I got stuck with a watery ending! I needed two courtesy flushes!
watery ending: define #2
watery ending
Adj.

A water crash landing in an airplane.
Flight attendant: “In case of a watery ending, the exits are to your left and right.” ::hand gestures::

Captain: “Ladies and gentelmen, please prepare for a watery ending.”

-euphoric captain voice-