"40 on your head" is an AAVE originating in basketball culture, and is a catchphrase for when an opposing player scores a high number of points on you in a humiliating fashion. It was further popularized during the 2023 NBA playoffs, when a kid in the crowd during a Sacramento Kings/Golden Warriors playoff game was seen on a national broadcast taunting player Steph Curry with the phrase after Kings star De'Aaron Fox had scored almost 40 points on him.
"He has 40. 40 on your head!"
by miscellany April 27, 2023