A mode of procrastination in which the individual, usually a student, in an effort to avoid starting homework, will go to the bathroom. Actual need to pee is irrelevant.
Jane: Ugh, I really don't want to start this paper. I guess I'll just go to the bathroom.
Jane's Roommate: Girl, you betterstop peecrastinating!
When you don't want to go back to work/whatever else you're doing, and proceed to stay on the toilet far too long looking at Facebook posts, Instagram pictures, news articles, playing 2048, etc. - often far longer than it has taken you to actually poop.
This may also be due to fear of wiping in some individuals.
Poopcrastinating in its various forms:
1) I had a bunch of TPS reports I didn't want to do, so I poopcrastinated on the toilet for a solid 20 minutes and got a new high score on candy crush.
2) I had a huge essay to write after I finished my Econ homework, but nature called and I proceeded to poopcrastinate for a half hour on instagram.
3) Person 1: "Where is Bob? He went to the bathroom a half an hour ago." Person 2: "He's probably poopcrastinating."