a fraternity brother who is especially obnoxious after consuming too much liquor, could also be used for someone who is acting is especially stupid due to over consumption of alcohol
Bro 1: Dude! I'm not sure if I was blacked out or if I hooked up with three chicks last nite.
Bro 2: No Bro! You were such a phitard you puked on three chicks and passed out by yourself.