The Collaborative International Dictionary of English v.0.48:

Platter \Plat"ter\, n. [From Plat to braid.]
   One who plats or braids.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Platter \Plat"ter\, n. [Probably fr. OF. platel, F. plateau. See
   Plateau.]
   A large plate or shallow dish on which meat or other food is
   brought to the table.
   [1913 Webster]

         The attendants . . . speedly brought in several large,
         smoking platters, filled with huge pieces of beef.
                                                  --Sir W.
                                                  Scott.
   [1913 Webster]

WordNet (r) 3.0 (2006):

platter
    n 1: a large shallow dish used for serving food
    2: sound recording consisting of a disk with a continuous
       groove; used to reproduce music by rotating while a
       phonograph needle tracks in the groove [syn: phonograph
       record, phonograph recording, record, disk, disc,
       platter]

Moby Thesaurus II by Grady Ward, 1.0:

28 Moby Thesaurus words for "platter":
   bulletin board, card, catalog card, disc, dish, file, filing card,
   film, index card, library catalog, magnetic tape, microcard,
   microdot, microfiche, microfilm, motion-picture film,
   phonograph record, plate, salver, scoreboard, scorecard,
   scoresheet, server, slip, tape, ticker tape, tray, videotape