radiolaria

plural noun

ra·​di·​o·​lar·​ia ˌrā-dē-ō-ˈler-ē-ə 

: protozoans that are radiolarians

Word History

Etymology

New Latin, from Late Latin radiolus small sunbeam, from diminutive of Latin radius ray — more at ray

First Known Use

1868, in the meaning defined above