When a man is having sex at the top of a flight of stairs then spits on the females back then when she turns around you blow it in her face then spartan kick her down the stairs and yell avalanche.
Yo, dude what happened last night I heard someone fall down the stairs? Yeah dude I gave that girl The avalanche
When two guys are having sex at the top of a staircase. Right as the "giver" (aka man on top) is about to erupt, he pushes his partener (the "taker") down the stairs as hard as he can yelling "AVALANCHE!".
*note: if done on top of a sleeping bag, this move works like a gem.
Guy #1: "Dude, what happened to your nose?"
Guy #2: "I bumped it last night while gary was giving me the avalanche."
when your fuckin a girl at the top of the stairs and right when you cum, you boot her ass down the stairs and yell avalanche!
Jon sent that bitch on The avalanche last night.