When you have to go poop so bad that it keeps coming partially out and you suck it back in to avoid messing your pants. This usually happens on a long trip, or when you can't get to a bathroom, or when it would be socially inappropriate to take a dump.
"I had to take a crap so bad I was prairiedogging like like a whackamole!" Or....."Me and Cheryl were out on a date and I had to take a crap so bad I was prairiedogging!"
When one's shit acts like a prarie dog, fanatically poking it's head in and out of it's home expressing it's urge to be freed from the confines of it's hole, but only when it is safe.
(See movie Rat Race)
Verb- The contraction of the ass sphincter to prevent an enormous shit from ejecting from the anus. The contraction usually takes place when the turd is slightly popped out. This contraction causes the turd to return inside the anus. Analogous to the motions of a prarie dog (hence the name) that sticks its head out of the ground and goes back into it.