The dirty turd is when you shit out only one turd but have to wipe your ass so much you use most of the toilet paper (if not all of it). That is why it is called the dirty turd.

the whale tail is the shape formed when a g-string rides up high over a womans trousers

A turd thats so super stinky and sticky that it fills not only the toilet with dirtines, but it leaves your butt hole, ass crack, and bathroom poopy.