The Collaborative International Dictionary of English v.0.48:

Actinozoa \Ac"ti*no*zo"a\, n. pl. [Gr. ?, ?, ray + zw^on
   animal.] (Zool.)
   A group of C[oe]lenterata, comprising the Anthozoa and
   Ctenophora. The sea anemone, or actinia, is a familiar
   example.
   [1913 Webster]

WordNet (r) 3.0 (2006):

Actinozoa
    n 1: a large class of sedentary marine coelenterates that
         includes sea anemones and corals; the medusoid phase is
         entirely suppressed [syn: Anthozoa, class Anthozoa,
         Actinozoa, class Actinozoa]