The Collaborative International Dictionary of English v.0.48:

Disc \Disc\ (d[i^]sk), 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.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Disk \Disk\ (d[i^]sk), n. [L. discus, Gr. di`skos. See Dish.]
   [Written also disc.]
   1. A discus; a quoit.
      [1913 Webster]

            Some whirl the disk, and some the javelin dart.
                                                  --Pope.
      [1913 Webster]

   2. A flat, circular plate; as, a disk of metal or paper.
      [1913 Webster]

   3. (Astron.) The circular figure of a celestial body, as seen
      projected of the heavens.
      [1913 Webster]

   4. (Biol.) A circular structure either in plants or animals;
      as, a blood disk; germinal disk, etc.
      [1913 Webster]

   5. (Bot.)
      (a) The whole surface of a leaf.
      (b) The central part of a radiate compound flower, as in
          sunflower.
      (c) A part of the receptacle enlarged or expanded under,
          or around, or even on top of, the pistil.
          [1913 Webster]

   6. (Zool.)
      (a) The anterior surface or oral area of c[oe]lenterate
          animals, as of sea anemones.
      (b) The lower side of the body of some invertebrates,
          especially when used for locomotion, when it is often
          called a creeping disk.
      (c) In owls, the space around the eyes.
          [1913 Webster]

   Disk engine, a form of rotary steam engine.

   Disk shell (Zool.), any species of Discina.
      [1913 Webster]

WordNet (r) 3.0 (2006):

disc
    n 1: 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]
    2: something with a round shape resembling a flat circular
       plate; "the moon's disk hung in a cloudless sky" [syn:
       disk, disc, 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,
       disc]
    4: a flat circular plate [syn: disk, disc]

The Free On-line Dictionary of Computing (19 January 2023):

disc
disc drive

    British spelling of "disk", normally
   only used for "compact disc".

   (1995-07-30)