Palaeechinoidea
plural noun
Palae·echinoidea
Definition of Palaeechinoidea
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 nounRead the Latest from M-W
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Origin and Etymology of palaeechinoidea
New Latin, from pale- + Echinoidea
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