Torpoodo

A torpedo shaped poop with a smooth body and low drag that plunges into a toilet with such propulsion that it disappears into the darkness of the deep waters, often out of the assailant's sight. This leaves the person with the feeling of essentially a phantom excrement.

-"Bro, I totally took a wicked dump, but when I looked into the toilet to evaluate my masterpiece, there was nothing there!"
-"That must've been one deadly torpoodo"