Definition of "radiolarian" [ra•di•o•la•ri•an]

• Any of various marine protozoans of the order Radiolaria, having rigid siliceous skeletons and spicules. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "The stone type quarried is unique to the Sarikaya quarry, as it can be microscopically classified as radiolarian mudstone."
• "The key to Haeckel's vision was a tiny undersea organism called the radiolarian, one of the earliest forms of life."
• "OTOH, how can you resist a guy who uses the word radiolarian in his lyrics?)"