An unwanted, somewhat aggressive approach in a club/dance hall/bar by a rather unattractive or drunk person, by method of dancing towards the victim, usually backwards, with the rear-end moving like the pendulum on a grandfather clock, gyrating up against the victim like the attacker was wiping their ass on the victims clothes.
Britney: "Holy crap, don't look"
Moesha: "What , what is it?"
Britney: "Damn girl, that fugly guy is looking at us. He's dancing like he's gonna do a boogie attack on me... eugh..."