The Collaborative International Dictionary of English v.0.48:

Gorgoniacea \Gor*go`ni*a"ce*a\, n. pl. [NL. See Gorgonia.]
   (Zool.)
   One of the principal divisions of Alcyonaria, including those
   forms which have a firm and usually branched axis, covered
   with a porous crust, or c[oe]nenchyma, in which the polyp
   cells are situated.
   [1913 Webster]

   Note: The axis is commonly horny, but it may be solid and
         stony (composed of calcium carbonate), as in the red
         coral of commerce, or it may be in alternating horny
         and stony joints, as in Isis. See Alcyonaria,
         Anthozoa, C[oe]nenchyma.
         [1913 Webster]

WordNet (r) 3.0 (2006):

Gorgoniacea
    n 1: red corals and sea fans [syn: Gorgonacea, suborder
         Gorgonacea, Gorgoniacea, suborder Gorgoniacea]