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opisthobranch

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noun opis·tho·branch \ ə-ˈpis-thə-ˌbraŋk \

Definition of opisthobranch

plural opisthobranchs
:any of a subclass (Opisthobranchia) of marine gastropod mollusks that have the gills when present posterior to the heart and often lack a shell
—

opisthobranch

adjective

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Origin and Etymology of opisthobranch

New Latin Opisthobranchia, from Greek opisthen behind (akin to Greek epi on) + branchia gills — more at epi-

Learn More about opisthobranch

  1. Britannica.com: Encyclopedia article about opisthobranch

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