A medical condition characterized by decreased airflow through the nasal cavity due to being packed full of shit. Common causes include: tossing salad, ramming one's nose up the boss' ass and having one's head up one's ass.
Hey Joe, It looks like you got poop snout since you ate Carl's ass.
When a dog's ( and sometimes people's) buttocks itch, they scoot on the floor to relieve the itch. On occasion this can be done at the same time as pooping, thus the name.