1. [n]  a manual control consisting of a vertical handle that can move freely in two directions; used as an input device to computers or to devices controlled by computers
2. [n]  a lever used by a pilot to control the ailerons and elevators of an airplane

A device consisting of a hand held stick that pivots about one end and transmits its angle in two dimensions to a computer. Joysticks are often used to control games, and usually have one or more push-buttons whose state can also be read by the computer. Most I/O interface cards for IBM PCs have a joystick (game control) port.