Gorgonia \Gor*go"ni*a\ (g[^o]r*g[=o]"n[i^]*[.a]), n. [L., a coral which hardens in the air.] (Zo["o]l.) 1. A genus of Gorgoniacea, formerly very extensive, but now restricted to such species as the West Indian sea fan ({Gorgonia flabellum}), sea plume ({G. setosa}), and other allied species having a flexible, horny axis. 2. Any slender branched gorgonian.