A plastic grocery bag full of all the loose or "mutt" beers in your fridge that you take over to a friends house instead of just picking up a case.
Joe: "do we gotta stop and get beer before we go to the party?"
Jeff: "naw we can put together a mutt bag, there are four or five keystones, three coors and a couple bud lights in the fridge."
Jeff: "naw we can put together a mutt bag, there are four or five keystones, three coors and a couple bud lights in the fridge."
by RJM '08 October 19, 2009