Basement or garage in which a close group of friends regularly hangs out. usually contains a old broken couch, sound system, Xbox, TV, whatever. Coined by Sam Bennett-Levy and Cory Sunshine in 2008
"lets go chill in the phat cave"
"i left my Bong in the phat cave last night, do you think you can get it back to me by tonight?"
"i think im just gonna' chill in the phat cave tonight"
"i just hooked up Xbox live in the phat cave!"