Plain English Meaning
A piece of navigation equipment that sits on the ground and sends out a signal. Aircraft pick up that signal and use it to figure out where they are or which way to fly.
Full Definition
A radio transmitter or beacon installed at a fixed location on the ground that broadcasts signals aircraft use to determine their position, track a course, or fly an approach. Examples include VOR, NDB, DME, TACAN, and ILS facilities.
Context Anchor
Seen in en route navigation and instrument procedure discussions, especially when a or procedure depends on signals sent from stations on the ground.