Palaeechinoidea

plural noun

Palae·​echinoidea

in some classifications

: a division of extinct chiefly Paleozoic sea urchins having the test usually composed of more than 20 meridional rows of plates that often overlap and jaws always present compare euechinoidea

palaeechinoidean

¦⸗⸗+

adjective or noun

Word History

Etymology

New Latin, from pale- + Echinoidea

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