free flopping
When a girl, specifically with large breasts, goes around in public or semi public without a bra on.
Whitney: "Alley, you are totally free flopping. I can see your nips and everything"
Alley: "Oh shit! I totally forgot! I'll go put a hoodie on to cover them up"
Alley: "Oh shit! I totally forgot! I'll go put a hoodie on to cover them up"