1) Animal order 2) Comprising the soft corals 3) Suborder alcyonacea 
Unlike stony corals, most soft corals thrive in nutrient-rich waters with less intense light. Almost all utilize symbiotic photosynthesizing zooxanthella as a major energy source. However, most will readily eat any free floating food, such as zooplankton, out of the water column. They are integral members of the reef ecosystem and provide habitat ...
• (n. pl.) A group of soft-bodied Alcyonaria, of which Alcyonium is the type. See Illust. under Alcyonaria.
(from the article `cnidarian`) ...and sea whips. Colonies commonly arborescent with axial skeleton of gorgonin and/or calcareous spicules. Polyps rarely dimorphic. Tropical and ...
Al`cy·o·na'ce·a noun plural [ New Latin ] (Zoology) A group of soft-bodied Alcyonaria, of which Alcyonium is the type. See Illust. under Alcyonaria . 
[n] - comprising the soft corals
suborder Alcyonacea noun comprising the soft corals