Errantia
plural noun
Er·ran·tia
| \ eˈranch(ē)ə, -ntēə\
Definition of Errantia
in some classifications
: a division of Polychaeta comprising free-swimming worms (such as those of the genera Aphrodite, Nereis, and Polynoe) usually with well-developed parapodia and sense organs and without special respiratory structures
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