ˌrādēˈäd.ə, -ˈād.ə noun plural
Usage: capitalized
Etymology: New Latin, from Latin, neuter plural of radiatus furnished with rays, from past participle of radiare to emit rays
in some classifications : a major category of invertebrates including forms having the parts arranged radially about an axis
a. in former classifications : all the radiate animals (as coelenterates, ctenophores, and echinoderms) together with a heterogeneous group (as sponges, bryozoans, and flatworms)
b. : the coelenterates and ctenophores which are regarded as fundamentally radiate in contrast to the secondarily radiate echinoderms — compare bilateria , dipleurula