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a phylum of marine invertebrates that includes sea anemones, hydras, jellyfish, and corals. See also coelenterata.
Cnidaria/Cni·da·ria/ (ni-dar´e-ah) a phylum of marine invertebrates including sea anemones, hydras, corals, jellyfish, and comb jellies, characterized by a radially symmetric body bearing tentacles around the mouth.
a phylum of invertebrate animals that includes jellyfish, sea anemones, hydroids, and corals. Formerly called Coelenterata.
Cnidariaa subphylum of the phylum Coelenterata in some classifications, where the Ctenophora (sea gooseberries) form the other subphylum (see COELENTERATE). However, in more modern classifications the Ctenophora are given the status of a phylum, so that the organisms classified in the Cnidaria (hydroids, jellyfishes, sea anemones and corals) are the only organisms in the new phylum Coelenterata, thus making the term Cnidaria obsolete.
a phylum of lowly animals including hydroids and hydromedusae (class Hydrozoa), true jellyfish and free-swimming medusae (class Scyphozoa) and sea anemones, sea pens and corals (class Anthozoa). Previously called Coelenterata and that name is still widely used.