slingshot

A Y-shaped stick with an elastic sling between the arms used for shooting small projectiles.

A stationary, often triangular object that launches any ball that hits its longest side back at a high force, now usually located above the flipper and between it and the inlane, with one each for both lower flippers.

To move or cause to move in a manner resembling a projectile shot from a slingshot.

(especially) To use the gravity of a moving planet to add momentum to a spacecraft.