artificial horizon

An instrument displaying a line on a flight indicator that lies within the horizontal plane and about which the pitching and banking movements of an aircraft are shown. Also called gyro horizon.

A device that provides the pilot with symbols representative of the attitude of an aircraft relative to an artificial horizon. In an automatic or artificial horizon a vertical gyro moves a horizon bar relative to a fixed aircraft index. Motion of the bar simulates changes in pitch or roll of the aircraft. As the pilot views the indicator, the horizon is seen relative to the aircraft as the horizon would appear if the pilot could see it through the windscreen. See also Gyroscope.

A device for indicating the horizon, as a bubble, pendulum or the flat surface of a liquid.

See attitude indicator.

The noun has one meaning:

Meaning #1: a navigational instrument based on a gyroscope; provides an artificial horizon for the pilot
  Synonyms: gyro horizon, flight indicator