What does "discoid" mean?

Discoid: Having the form of a disk, as those univalve shells which have the whorls in one plane, so as to form a disk, as the pearly nautilus. Discoid flower (Bot.), a compound flower, consisting of tubular florets only, as a tansy, lacking the rays which are seen in the daisy and sunflower.

Additional senses

  1. 2.Anything having the form of a discus or disk; particularly, a discoid shell.

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