The Collaborative International Dictionary of English v.0.48:

Turntable \Turn"ta`ble\, n.
   A large revolving platform, for turning railroad cars,
   locomotives, etc., in a different direction; -- called also
   turnplate.
   [1913 Webster]

WordNet (r) 3.0 (2006):

turntable
    n 1: a circular horizontal platform that rotates a phonograph
         record while it is being played
    2: a revolving tray placed on a dining table [syn: turntable,
       lazy Susan]
    3: a rotatable platform with a track; used to turn locomotives
       and cars

Moby Thesaurus II by Grady Ward, 1.0:

45 Moby Thesaurus words for "turntable":
   Gramophone, PA, PA system, Victrola, audio sound system,
   audiophile, binaural system, bitch box, bullhorn, cartridge,
   ceramic pickup, changer, crystal pickup,
   derived four-channel system, discrete four-channel system,
   four-channel stereo system, hi-fi, hi-fi fan, high-fidelity,
   intercom, intercommunication system, jukebox, magnetic pickup,
   monaural system, mono, needle, nickelodeon, phonograph,
   photoelectric pickup, pickup, public-address system,
   quadraphonic sound system, radio-phonograph combination,
   record changer, record player, sound reproduction system,
   sound truck, squawk box, stereo, stylus, system, tape deck,
   tape recorder, tone arm, transcription turntable