Commomnly used in Northern Minnesota, it's when someone is passed out,(prefferably in the upright position), then some daring party-goer lowers their pants and sticks their bare asshole on the tip of the passed out person's nose. Then you reach around and give the passed out person a good slap on the face, waking them up. This results in the person springing forward, essentially giving themselves a full facefull of ass.

When you eat dirt for the first time and leave your family to build a shack in the woods