What does ground speed refer to in aviation?

Ground speed refers specifically to the speed of an aircraft in relation to the surface of the Earth. This measurement takes into account not just the aircraft's own speed through the air, but also the influence of wind—either helping or hindering its progress over the ground.

Understanding ground speed is crucial for flight planning and navigation, as it directly affects the estimated time of arrival at the destination. While the aircraft may be moving at a certain speed through the air (true airspeed), the ground speed reflects how quickly it is actually covering distance across the Earth’s surface.

The other definitions provided serve different contexts in aviation: speed relative to the air pertains to true airspeed, total speed considering wind effects relates to calculating ground speed, and speed in relation to the destination involves factors such as air traffic control management and navigation but is not a direct definition of ground speed itself.