Source : Webster's Revised Unabridged Dictionary (1913)

Disc \Disc\, n. [See {Disk}, {Dish}.]
   A flat round plate; (Biol.) A circular structure either in
   plants or animals; as, a blood disc, a germinal disc, etc.
   Same as {Disk}.

Source : WordNet®

disc
     n 1: sound recording consisting of a disc with continuous
          grooves; formerly used to reproduce music by rotating
          while a phonograph needle tracked in the grooves [syn: {phonograph
          record}, {phonograph recording}, {record}, {disk}, {platter}]
     2: something with a round shape like a flat circular plate
        [syn: {disk}, {saucer}]
     3: (computer science) a memory device consisting of a flat disk
        covered with a magnetic coating on which information is
        stored [syn: {magnetic disk}, {magnetic disc}, {disk}]
     4: a flat circular plate [syn: {disk}]

Source : Free On-Line Dictionary of Computing

disc
     
         British spelling of "{disk}", normally
        only used for "{compact disc}".
     
        (1995-07-30)