plural noun

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
adjective or noun

Word History


New Latin, from pale- + Echinoidea

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Dictionary Entries Near Palaeechinoidea

Cite this Entry

“Palaeechinoidea.” Dictionary, Merriam-Webster, Accessed 20 Feb. 2024.

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