ground speed

n. g.s., speed of a flying aircraft relative to the ground it crosses in a given period of time

Ground speed is the speed of an aircraft relative to the ground. It is the sum of the aircraft's true airspeed and the current wind and weather conditions; a headwind subtracts from the ground speed, while a tailwind adds to it. Winds at other angles to the heading will have components of either headwind or tailwind as well as a crosswind component.
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The speed of an aircraft relative to the surface of the earth. (FAA4)

The horizontal component of the speed of an aircraft relative to the earth's surface. 1/11/75

Composante horizontale de la vitesse d'un aéronef par rapport à la surface terrestre. 1/11/75

The speed of an aircraft relative to the surface of the earth.