Cnidaria, Coelenterata, phylum Cnidaria, phylum Coelenterata - hydras; polyps; jellyfishes; sea anemones; corals

scyphozoan - any of various usually free-swimming marine coelenterates having a gelatinous medusoid stage as the dominant phase of its life cycle

Chrysaora, genus Chrysaora - a genus of Scyphozoa

class - (biology) a taxonomic group containing one or more orders