The Collaborative International Dictionary of English v.0.48:

Gorgonian \Gor*go"ni*an\, a. [L. Gorgoneus.]
   1. Pertaining to, or resembling, a Gorgon; terrifying into
      stone; terrific.
      [1913 Webster]

            The rest his look
            Bound with Gorgonian rigor not to move. --Milton.
      [1913 Webster]

   2. (Zool.) Pertaining to the Gorgoniacea; as, gorgonian
      coral.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Gorgonian \Gor*go"ni*an\, n. (Zool.)
   One of the Gorgoniacea.
   [1913 Webster]

WordNet (r) 3.0 (2006):

gorgonian
    n 1: corals having a horny or calcareous branching skeleton
         [syn: gorgonian, gorgonian coral]