plural noun Opis·tho·bran·chia

Definition of Opisthobranchia


  1. :  a large order of Euthyneura comprising marine gastropod mollusks having the gills when present posterior to the heart and having no operculum — compare streptoneura — see nudibranchia, tectibranchia


adjective or noun

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Origin and Etymology of opisthobranchia

New Latin, from opisth- + -branchia

Seen and Heard

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feeling or affected by lethargy

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