backboard
The flat board behind a basketball hoop that the ball hits.
A backboard is the flat, rectangular board mounted behind a basketball hoop. When you shoot a basketball, you can bounce it off the backboard to help guide it into the basket. This technique, called a bank shot, uses the board's surface as a tool to score from tricky angles.
The backboard serves several purposes. It gives players another way to make baskets, especially during layups when they're close to the hoop. It also stops the ball from flying too far when someone misses a shot, keeping the game moving. Many backboards are made of transparent material so fans sitting behind them can still see the action.