radio
noun
ˈreɪdiəʊ 
ˈreɪdioʊ 
1 (often the radio) [uncountable, singular] the activity of broadcasting programmes for people to listen to; the programmes that are broadcastThe interview was broadcast on radio and television.The play was written specially for radio.I listen to the radio on the way to work.Did you hear the interview with him on the radio?local/national radioa radio programme/station2 [countable] a piece of equipment used for listening to programmes that are broadcast to the publicto turn the radio on/offa car radioa radio cassette player see also clock radio3 [uncountable] the process of sending and receiving messages through the air using electromagnetic wavesHe was unable to contact Blake by radio.to keep in radio contactradio signals/waves4 [countable] a piece of equipment, for example on ships or planes, for sending and receiving radio signalsto hear a gale warning on/over the ship's radio