opisthobranchia Meaning, Definition & Usage

  1. noun gastropods having the gills when present posterior to the heart and having no operculum: includes sea slugs; sea butterflies; sea hares
    subclass Opisthobranchia.

WordNet

O*pis`tho*bran"chi*a, O*pis`tho*bran`chi*a"ta noun plural (Also<
  • Opisthobranchia
  • Opisthobranchiata
)
Etymology
NL., from Gr. behind + gills.
Definitions
  1. (Zoöl.) A division of gastropod Mollusca, in which the breathing organs are usually situated behind the heart. It includes the tectibranchs and nudibranchs.

Webster 1913