The Collaborative International Dictionary of English v.0.48:

Radio- \Ra"di*o-\ (r[=a]"d[i^]*[-o]-), a.
   1. Of or pertaining to, or employing, or operated by, radiant
      energy, specifically that of electromagnetic waves with
      frequencies between those of infrared radiation and
      X-rays; hence, pertaining to, or employed in, broadcast
      radio or television, microwaves, radiotelephones, etc.;
      as, radio waves.
      [Webster 1913 Suppl. +PJC]

   2. of or pertaining to broadcast radio; as, a radio program.
      [PJC]

The Collaborative International Dictionary of English v.0.48:

Radio- \Ra"di*o-\ (r[=a]"d[i^]*[-o]-).
   A combining form indicating connection with, or relation to,
   a radius or ray; specifically (Anat.), with the radius of the
   forearm; as, radio-ulnar, radio-muscular, radio-carpal.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

electronic device \electronic device\ n.
   a device depending on the principles of electronics and using
   the manipulation of electron flow for its operation.
   [PJC]

   Note: Numerous electronic devices are in daily use, among
         them the television, radio, computer, robot,
         transmitter, receiver, VCR, CD player, etc.
         [PJC]

WordNet (r) 3.0 (2006):

radio
    adj 1: indicating radiation or radioactivity; "radiochemistry"
    n 1: medium for communication [syn: radio,
         radiocommunication, wireless]
    2: an electronic receiver that detects and demodulates and
       amplifies transmitted signals [syn: radio receiver,
       receiving set, radio set, radio, tuner, wireless]
    3: a communication system based on broadcasting electromagnetic
       waves [syn: radio, wireless]
    v 1: transmit messages via radio waves; "he radioed for help"

Moby Thesaurus II by Grady Ward, 1.0:

155 Moby Thesaurus words for "radio":
   AM receiver, AM tuner, AM-FM receiver, AM-FM tuner, CB, RDF,
   Teletype, Wirephoto, advice, adviser, air, announce, announcer,
   annunciator, audio-frequency, authority, auto radio, automation,
   aviation radio, avionics, battery radio, beam, broadcast,
   broadcast journalism, cabinet, cable, channel, chassis,
   citizens band, communicant, communication, communicational,
   communications, communicator, console, crystal set, disseminate,
   electron microscopy, electron optics, electron physics,
   electronic engineering, electronics, electrophysics, enlightener,
   expert witness, facsimile, flash, gossipmonger, grapevine,
   heterodyne, high-frequency, housing, informant, information,
   information center, information medium, informer, intelligence,
   interviewee, journalism, line radio, magnetotelephonic,
   microtelephonic, monitor, monotelephonic, mouthpiece,
   multiplex receiver, news, news agency, news medium, news service,
   newscast, newsiness, newsletter, newsmagazine, newsmonger,
   newspaper, newsworthiness, notifier, photoelectricity,
   phototelegraphic, pocket radio, present, press, press association,
   public relations officer, publisher, radar, radiate,
   radio direction finder, radio receiver, radio set, radio telescope,
   radio-record player, radiobroadcast, radionics, radiophone,
   radiophotography, radiotelegraphic, radiotelegraphy,
   radiotelephony, railroad radio, receiver, receiving set,
   regenerative receiver, relay receiver, reportage, reporter, send,
   send a wire, set, ship-to-shore radio, shortwave, sign off,
   sign on, signal, source, spokesman, sportscast, superheterodyne,
   table radio, telecommunicational, telegram, telegraph,
   telegraph agency, telegraphic, telephonic, telephotographic,
   television, telex, teller, the fourth estate, the press,
   thermotelephonic, tidings, tipster, tout, transceiver, transistor,
   transistor physics, transmit, transmit-receiver, tuner,
   walkie-talkie, wire, wire service, wire wave communication,
   wired radio, wired wireless, wireless, wireless set,
   wireless telegraphy, wireless telephony, witness, word