Plain English Meaning

COM1 is the name given to the first of the airplane's voice radios. Pilots use it to talk to controllers and other pilots. If the airplane has a second radio, that one is called COM2.

Full Definition

COM1 is the label for the primary VHF communication radio in an aircraft, used to transmit and receive voice communications with air traffic control, flight service stations, and other aircraft on assigned frequencies. When two communication radios are installed, they are typically labeled COM1 and COM2, with COM1 normally selected as the active radio for the current controlling agency.

Context Anchor

You see COM1 on radio displays, audio panels, avionics screens, and when choosing which radio to use for communication.