2.)When someone has already given you a beer.
3.)When the foam from a beer gets on your chin, thus having a beer beard, known as a beerd.
-Jose:"Hey I'm going back in the house you need a beer?"
Marty:"Naw man I've already been beerd."
-I wonder why those chicks keep giggling and looking down here? Ah I gotta take a piss...<Looks in mirror sees a beerd on his chin> Shit!...