noun

1. a thin, flat, circular thing of any material
2. anything like this in form the moon's disk
3. any of the sharp, circular blades of a disk harrow
4. Anat. a layer of fibrous connective tissue with small masses of cartilage among the fibers, occurring between adjacent vertebrae
5. Bot.
   1. disk flower
   2. a circular nectary around the center of some flowers
6. a thin, flat, circular plate coated with ferromagnetic particles, on which computer data can be stored
7. disc
8. Obsolete discus

Etymology: L discus: see discus