Definition
A fixed, ground-based radio transmitter that broadcasts VHF navigation signals on assigned frequencies between 108.0 and 117.95 MHz. The station radiates two signals -- a reference signal and a variable signal -- that allow an aircraft's VOR receiver to determine the aircraft's bearing from the station along any of 360 radials.
Plain English
A radio transmitter on the ground that sends out signals an aircraft can use to find its direction from that point. Each station has its own frequency, and the signals work like spokes on a wheel radiating outward in every direction.
Context Anchor
You encounter this term when learning VOR navigation, tuning a VOR frequency, identifying the station, or following a course based on that station.
Derivation
VOR stands for VHF Omnidirectional Range. 'Omnidirectional' comes from Latin omnis (all) and 'directional' -- meaning the station transmits useful signals in all directions, not just one. 'Range' here is the older aviation sense of a navigation beam or course, not 'distance.'
Why Pilots Care
Provides reliable navigation guidance and defined airways independent of GPS.
Intuition Check
“Ground station” does not mean the airport ground-control radio position or a station you talk to. Here it means a fixed radio transmitter site used for navigation.
Example Sentence 1
After takeoff we tuned the VOR ground station at Dubuque on 108.8 and tracked the 270 radial westbound.
Example Sentence 2
While flying the airway the aircraft remained on the 090 radial from the VOR ground station.