Definition
A satellite-based radio navigation system operated by the U.S. Department of Defense that provides users with continuous position, velocity, and time information anywhere on or near the Earth. A GPS receiver determines its location by measuring the precise time delay of signals received from multiple satellites in known orbits, then calculating its position in three dimensions.
Plain English
A navigation system that uses signals from satellites in space to tell a receiver exactly where it is on Earth, how fast it's moving, and what time it is.
Context Anchor
Pilots encounter GPS on cockpit navigation displays, moving maps, flight plans, and some instrument approach procedures.
Derivation
From Latin globus (round mass, sphere) and positio (placement). 'Global Positioning' literally means 'finding your place anywhere on the globe' — which is exactly what the system does.
Why Pilots Care
Gives accurate position information in all weather and terrain, reducing dependence on older ground-based navigation aids and supporting safer, more direct flight paths.
Analogy
GPS works a little like finding your position by measuring your distance from several known points. The receiver uses satellites as those known points.
Intuition Check
Do not assume GPS means the aircraft is automatically cleared or safe to go anywhere. GPS gives position information; the pilot must still follow procedures, airspace rules, and equipment limits.
Example Sentence 1
The pilot loaded the direct route into the GPS and flew straight to the destination airport.
Example Sentence 2
GPS allowed the flight to proceed direct to the destination after the controller cleared the route change.