any invertebrate animal of the phylum Coelenterata, including the hydras, jellyfishes, sea anemones, and corals, characterized by a single internal cavity serving for digestion, excretion, and other functions and having tentacles on the oral end.
On the whole, however, the coelenterate fauna is rather meager and colorless.
British Dictionary definitions for coelenterate
any invertebrate of the phylum Cnidaria (formerly Coelenterata), having a saclike body with a single opening (mouth), which occurs in polyp and medusa forms. Coelenterates include the hydra, jellyfishes, sea anemones, and corals
(loosely) any invertebrate of the phyla Cnidaria or Ctenophora
of or relating to coelenterates
coelenteric (ˌsiːlɛnˈtɛrɪk) adjective
C19: from New Latin Coelenterata, hollow-intestined (creatures); see coel-, enteron