Definition
A combined avionics unit that provides both VHF voice communication with air traffic control and other stations, and VHF navigation reception (typically VOR, localizer, and glideslope signals) used for course guidance. Often called a 'nav/com,' it integrates two functions — talking and navigating — into a single radio with separate frequency selectors and audio outputs for each side.
Plain English
A single piece of cockpit equipment that does two jobs at once: it lets the pilot talk on the radio, and it receives signals from ground stations that show the aircraft where it is and which way to fly.
Context Anchor
Seen in instrument flying when a pilot tunes cockpit radios for air traffic control communication and radio-based navigation.
Derivation
Navigation comes from older words meaning to direct or manage a ship. Communication comes from a word meaning to share or make common. In this term, the radio supports both ideas: finding the way and sharing messages.
Why Pilots Care
It provides the primary means to stay in contact with air traffic control and to receive electronic navigation guidance without needing separate radios for each task.
Intuition Check
Do not read the slash as meaning the radio does only one blended job. It means the unit has two related jobs: navigation receiving and voice communication.
Example Sentence 1
Before takeoff, the pilot tuned the tower frequency on the COM side of the navigation/communication radio and set the VOR frequency for the departure procedure on the NAV side.
Example Sentence 2
In cruise the navigation/communication radio continued to receive navigation signals while the pilot requested a route change from center.