Cyathophylloid /(s?`?-th?-f?l"loid)/

Cy·a·tho·phyl·loid

Cyathophylloid

a.
  1. Like, or pertaining to, the family Cyathophyllidæ. (Paleon.)

Cyathophylloid

n.
  1. A fossil coral of the family Cyathophyllidæ; sometimes extended to fossil corals of other related families belonging to the group Rugosa; -- also called cup corals. Thay are found in paleozoic rocks. (Paleon.)