a voice from the heavens; incorporeal speech.

a message sent by wireless communication; wireless.

radio - a) the practice or science of communicating over a distance by converting sounds or signals into electromagnetic waves and transmitting these directly through space, without connecting wires, to a receiving set, which changes them back into sounds, signals, etc.; b) broadcasting by radio as an industry, entertainment, art, etc.; c) all the facilities and related activities of such broadcasting.

a kind of stringed musical instrument.