When a woman (usually overweight) bends over and shows the world more than expected. Her ass is on display and there is usually a thin red or pink thong hanging half way up her ass.
Hey Roger I was at the kitchen in the office and Mimi from payroll dropped her diet coke. I heard it hit the ground and turned around and saw her bent over and her whole ass hanging out of her pants. I was like "Oh my God, Moon over Miami"