n.
Pronunciation: ˌ r ā -d ē - ō - ' ler- ē - ə n
Function: noun
Date: 1875
: 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
radiolarian