Discoid /(?)/

Dis·coid

Discoid

a.
  1. 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.

Phrases & Compounds
Discoid flower
a compound flower, consisting of tubular florets only, as a tansy, lacking the rays which are seen in the daisy and sunflower.

Discoid

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