originated at Michigan State University from a suburban kid from the most isolated town in America who easily lives the most pathetic lifestyle possible consisting of 4 half gallons of rum a week. the word can simply mean any form of drunken shenanigans. For example being drunk, blacking out, sending mass text messages of the word "en toast" all qualify. Anything is fair game.
Man you peed in the hallway of that apartment and punched out a light last night man, you were really drunk...yep i was en toasted as shit.