The act of slamming down food and drink in a disorderly fashion, whilst totally lacking all manners in order to quickly satisfy a huge bout of hunger.
Most likely the act of an anorexic who's sick of doing the "heave bread to stay skinny" routine, or just someone who's freakishly hungry.
Dude1: Check that guy out over there. He's freakin' chowing that. That's like his eighth plate!
Dude2: Damn. He's slamming that like he hasn't eaten in a week!