Tilt refers to the anti-cheat mechanism in modern pinballs.
The tilt mechanism is controlled by a tilt pendulum, haning under the playfield, encircled by a loop. As the player nudges and pushes the cabinet during gameplay, the pendulum swings. If the rod of the pendulum makes contact with the circuit enclosing it, a tilt warning is given. After a certain number of warnings (usually at the third), the game tilts, turning off the power to the flippers, causing the ball to drain. This also forfeits any bonus accumulated on the current ball.