radiolarian

[ rey-dee-oh-lair-ee-uh n ]

/ ˌreɪ di oʊˈlɛər i ən /

noun

any minute, marine protozoan of the class Radiolaria, or, in some classification schemes, the superclass Actinopoda, having an amebalike body with radiating, filamentous pseudopodia and a usually elaborate outer skeleton.

Nearby words

Origin of radiolarian

1875–80; < New Latin Radiolari(a) name of the group (Latin radiol(us) a small beam, equivalent to radi(us) radius + -olus -ole¹ + -aria -aria) + -an

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for radiolarian

A larger number of new forms has been found in the Radiolarian ooze collected by the Challenger, and others fossil in Barbados.
Report on the Radiolaria Collected by H.M.S. Challenger During the Years 1873-1876, Second Part: Subclass Osculosa; Index|Ernst Haeckel
This remarkable species is the oldest known skeleton of a Radiolarian, a figure of it being given in 1838, loc.
Report on the Radiolaria Collected by H.M.S. Challenger During the Years 1873-1876, Second Part: Subclass Osculosa; Index|Ernst Haeckel
The whole number of Radiolarian genera distinguished in that first system was forty-four.
Report on the Radiolaria Collected by H.M.S. Challenger During the Years 1873-1876, First Part: Porulosa (Spumellaria and Acantharia)|Ernst Haeckel
Hence it may be supposed that a large part of the red clay consists of decomposed Radiolarian ooze.
Report on the Radiolaria Collected by H.M.S. Challenger During the Years 1873-1876, First Part: Porulosa (Spumellaria and Acantharia)|Ernst Haeckel

To him a radiolarian, or any other creature, is of interest, not so much on its own account as for its associations.
A History of Science, Volume 5(of 5)|Henry Smith Williams

British Dictionary definitions for radiolarian

radiolarian

/ (ˌreɪdɪəʊˈlɛərɪən) /

noun

any of various marine protozoans constituting the order Radiolaria, typically having a siliceous shell and stiff radiating cytoplasmic projections: phylum Actinopoda (actinopods)

Word Origin for radiolarian

C19: from New Latin Radiolaria, from Late Latin radiolus little sunbeam, from Latin radius ray, radius

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for radiolarian

radiolarian

1862, from Radiolaria, Modern Latin classification name, from Latin radiolus, diminutive of radius (q.v.).

Science definitions for radiolarian

radiolarian

[ rā′dē-ō-lâr′ē-ən ]

Any of various marine protozoans of the group Radiolaria, having rigid skeletons usually made of silica. The skeletons are usually spherically symmetrical and structurally complex, containing elaborate patterns of perforations (through which pseudopods extend) and often spicules. Skeletal remains of radiolarians sink to form ooze on the ocean floor, and prehistoric radiolarian ooze has fossilized to become chert and flint.