Radio is a way of transmitting sound using electromagnetic waves called radio waves. Nowadays, people usually only listen to the radio as they drive, but — before television — radio provided prime-time entertainment.

When you turn on your car radio, you probably take for granted the many choices of music and talk stations you can choose from. The radio's electronic components do the amazing job of catching fast-moving radio waves in the air and translating them into sounds you can hear. Radios were originally called wireless because they transmit energy using waves instead of wires. The Latin root of radio is radius, "beam."

Definitions of radio
  1. noun
    medium for communication
    synonyms: radiocommunication, wireless
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    type of:
    taking part in a radio or tv program
  2. noun
    an electronic receiver that detects and demodulates and amplifies transmitted signals
    synonyms: radio receiver, radio set, receiving set, tuner, wireless
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    show 4 types...
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    clock radio
    a radio that includes a clock that can be set to turn it on automatically
    crystal set
    an early radio receiver using a crystal detector
    heterodyne receiver, superhet, superheterodyne receiver
    a radio receiver that combines a locally generated frequency with the carrier frequency to produce a supersonic signal that is demodulated and amplified
    push-button radio
    a radio receiver that can be tuned by pressing buttons
    type of:
    receiver, receiving system
    set that receives radio or tv signals
  3. noun
    a communication system based on broadcasting electromagnetic waves
    synonyms: wireless
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    radiotelegraph, radiotelegraphy, wireless telegraph, wireless telegraphy
    the use of radio to send telegraphic messages (usually by Morse code)
    type of:
    communication system
    a system for communicating
  4. verb
    transmit messages via radio waves
    “he radioed for help”
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    type of:
    communicate, intercommunicate
    transmit thoughts or feelings
  5. adjective
    indicating radiation or radioactivity
Word Family

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