radiolarian

noun

ra·​di·​o·​lar·​i·​an ˌrā-dē-ō-ˈler-ē-ən How to pronounce radiolarian (audio)
: any of three classes (Acantharia, Polycystina, and Phaeodaria) of usually spherical chiefly planktonic marine protozoans having radiating threadlike pseudopodia and often a siliceous skeleton of spicules
radiolarian adjective

Illustration of radiolarian

Illustration of radiolarian

Examples of radiolarian in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
At left, a large Thalassicolanucleata radiolarian with a central capsule enclosing the nucleus. Discover Magazine, 3 June 2015 The organic carbon decline coincided with the disappearance of more than 50 species of radiolarians, which served as a food source for numerous marine species and whose disappearance was an indicator of a major biological crisis. Reuters, WIRED, 10 May 2001

Word History

First Known Use

1869, in the meaning defined above

Time Traveler
The first known use of radiolarian was in 1869

Dictionary Entries Near radiolarian

Cite this Entry

“Radiolarian.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/radiolarian. Accessed 26 Nov. 2024.

Kids Definition

radiolarian

noun
ra·​di·​o·​lar·​i·​an ˌrād-ē-ō-ˈlar-ē-ən How to pronounce radiolarian (audio)
-ˈler-
: any of various usually ball-shaped marine protozoans that have small spines radiating from the shell and have a skeleton containing silica

More from Merriam-Webster on radiolarian

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!