flashing pumkins
Verb: When somebody flashes their C cup+ breasts. It's a pun for smashing pumkins (the band or the act, changes based on context).
Guy 1: "Yo man this bitch hella fine"
Guy 2: "Yeah dude I saw her doing the flashing pumkins the other day, she got some big ol' titties"
Guy 2: "Yeah dude I saw her doing the flashing pumkins the other day, she got some big ol' titties"