1. A communication system based on broadcasting electromagnetic waves
   "ships use radio to send distress signals";
   - wireless, radiocommunication
    
2. An electronic receiver that detects and demodulates and amplifies transmitted signals
   "The radio was set to her favourite station";
   - radio receiver, receiving set, radio set, tuner, wireless
    
3. The activity or industry of radio broadcasting
   "She works in radio"
    
4. A radio broadcast or program
   "We listened to the morning radio"
    
5. An electromagnetic wave frequency between audio and infrared (about 3 kHz to 300 GHz)
   "Emission in the radio revealed a new type of star"; "The radio station broadcast on a radio frequency of 98.5 MHz";
   - radio frequency

1. Transmit messages via radio waves
   "he radioed for help"

1. Indicating radiation or radioactivity
   "The scientists used radio tracers to study the plant's nutrient uptake"
    
2. Operating at or relating to radio-frequency electromagnetic waves
   "The telescope detected radio emissions from the galaxy"

Derived forms: radioing, radioes, radios, radioed

Type of: broadcasting, communicate, communication system, frequence, frequency, intercommunicate, oftenness, receiver, receiving system

Part of: electromagnetic spectrum, radio-gramophone, radio-phonograph

Encyclopedia: Radio, Radio