ˌrādēōˈla(a)rēə noun plural
Usage: capitalized
Etymology: New Latin, from Late Latin radiolus small sunbeam (diminutive of Latin radius ray, beam) + New Latin -aria — more at ray
: a large order of rhizopods having protoplasm that is divided into an inner nucleated portion enclosed in a perforated membrane of chitinous material and an outer vacuolated portion from which radiate threadlike pseudopodia, usually a horny or siliceous skeleton composed of spicules that may unite to form a basket-shaped structure, and numerous symbiotic unicellular yellow algae scattered in the protoplasm — compare zooxanthella