a nonmagnetic compass that uses a motor-driven gyroscope to indicate true north
Sometimes shortened to: gyro
gyrocompass in American English
(ˈdʒaɪroʊˌkʌmpəs; ˈdʒaɪrəˌkʌmpəs)
noun
a compass consisting of a motor-operated gyroscope whose rotating axis, kept in a horizontal plane, takes a position parallel to the axis of the earth's rotation and thus points to the geographical north pole instead of to the magnetic pole