When playing basketball, they way someone sticks out their booty really exaggerated when dribbling, in triple threat, or about to shoot. Their back is arched backwards too far and their knees are low and wide apart. Looks like they're about to booty dance. Mostly, and hopefully, found in females.
Oohh damn you see number 24? She got a serious case of Basketball Booty!" "I know! She looks like she's finna break her back!