Illustration of radiolarian
radiolarian
noun
ra·di·o·lar·i·an
ˌrā-dē-ō-ˈler-ē-ən 
: 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
Examples of radiolarian in a Sentence
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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
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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
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“Radiolarian.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/radiolarian. Accessed 19 Feb. 2025.
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radiolarian
noun
ra·di·o·lar·i·an
ˌrād-ē-ō-ˈlar-ē-ən
-ˈler-
: any of various usually ball-shaped marine protozoans that have small spines radiating from the shell and have a skeleton containing silica
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