plural noun

ra·​di·​o·​lar·​ia ˌrā-dē-ō-ˈler-ē-ə How to pronounce radiolaria (audio)
: protozoans that are radiolarians

Word History


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

Time Traveler
The first known use of radiolaria was in 1868

Dictionary Entries Near radiolaria

Cite this Entry

“Radiolaria.” Dictionary, Merriam-Webster, Accessed 13 Jul. 2024.

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