Often when someone spills or breaks or drops something at a party (often resulting in a mess or general spectacle), or when someone does something embarassing or dumb.
Usually accompanied by someone actually yelling, "Party Foul!" while everyone else laughs because they're drunk.
1. An action committed by an individual, either on purpose or not, that goes against the feel of the party or bar atmosphere.
2. To spill an alcoholic drink.
When something stupid, embarrassing, or simply unacceptable is done at a party. Examples of this include spilling beer, breaking a lamp, throwing up, getting so drunk that you scoot on the floor in just your boxers, choking on a shot, ect.
a person who fucks up a party due to his inability to handle his drinks, consequently making a complete ass of himself by constantly provoking fights and screaming "LET'S GOOOOOOOO" at every guy, girl, cops, cats, dogs, chairs, lamps, etc.