Real Dictionary

gyroscope
countable noun: A gyroscope is a device that contains a disc turning on an axis that can turn freely in any direction, so that the disc maintains the same position whatever the position or movement of the surrounding structure.

gyroscope in American English
a wheel mounted in a set of rings so that its axis of rotation is free to turn in any direction: when the wheel is spun rapidly, it will keep the original direction of its rotation axis no matter which way the ring is turned: gyroscopes are used in gyroco
noun: an apparatus consisting of a rotating wheel so mounted that its axis can turn freely in certain or all directions, and capable of maintaining the same absolute direction in space in spite of movements of the mountings and surrounding parts: used to mainta

gyroscope in British English
noun: a device containing a disc rotating on an axis that can turn freely in any direction so that the disc resists the action of an applied couple and tends to maintain the same orientation in space irrespective of the movement of the surrounding structure