Mechanical instrument, used as a stabilizing device and consisting, in its simplest form, of a heavy wheel mounted on an axis. The direction of the axis is stable; if it is displaced, the gyroscope tends to resist the change. Applications of the gyroscope principle include the gyrocompass, the autopilot for automatic control of an aircraft, and gyro-directed torpedoes.
The star, which was added to the flag in 1793, initially had more than five points. The star may represent the Morning Star mentioned in the Koran. Effective date: 5 June 1936.