Date: 1900-2000 Origin: radiotelegraphy (19-21 centuries), from radio- + telegraphy radio1 noun Related topics: Television and Radio, Broadcastingra???di???o1 S1 W21a) [countable]TCB a piece of electronic equipment which you use to listen to programmes that are broadcast, such as music and news turn/switch the radio on/off I sat down and turned on the radio.b) [uncountable]AMT programmes that are