Very high frequency Omnidirectional Range. A radio navigation aid operating in the 108-118 MHz band. A VOR ground station transmits a two-phase directional signal through 360 Found on http://airodyssey.net/reference/glossary/
VHF OmniRange. A ground-based navigation aid transmitting very high-frequency (VHF) navigation signals 360 Found on http://www.aerofiles.com/glossary.html