‖n. pl. [ Gr. &unr_;, &unr_;, ray + zw^, on animal. ] (Zool.) A group of Cœlenterata, comprising the Anthozoa and Ctenophora. The sea anemone, or actinia, is a familiar example. [ 1913 Webster ]
(n) a large class of sedentary marine coelenterates that includes sea anemones and corals; the medusoid phase is entirely suppressed, Syn. Actinozoa, class Anthozoa, class Actinozoa