opis·​tho·​branch | \ ə-ˈpis-thə-ˌbraŋk How to pronounce opisthobranch (audio) \
plural opisthobranchs

Definition of opisthobranch

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

Other Words from opisthobranch

opisthobranch adjective

First Known Use of opisthobranch

1851, in the meaning defined above

History and Etymology for opisthobranch

borrowed from French opistobranches, plural, from Greek opistho-, combining form from ópisthen "behind, in back" + French -branches, borrowed from New Latin -brancha or -branchia "having gills (of the kind specified)," based on Latin branchia "gills," borrowed from Greek bránchia; ópisthen variant (with -s- after prósthen "before, in front" and opísō "backward") of ópithen, from opi- (going back to Mycenaean Greek o-pi "on, for," going back to Indo-European *h1opi, o-grade form of *h1epi "on") + -the(n), going back to Indo-European *dhe, locative particle — more at branchial, epi-

Note: The vernacular taxonomic name opistobranches (later Latinized as Opisthobranchia, with the erroneous spelling -st- corrected to -sth-) was introduced by the French zoologist Henri Milne-Edwards (1800-85). It appears first in a report to the Société Philomathique de Paris, Extraits des procès-verbaux des séances pendant l'année 1846, Séance du 1er août 1846, p. 116, and in a more detailed presentation in "Notes sur la classification naturelle des mollusques gastéropodes," Annales des sciences naturelles, 3. série (Zoologie), tome 9. (1848), pp. 102-12.

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The first known use of opisthobranch was in 1851

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Cite this Entry

“Opisthobranch.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/opisthobranch. Accessed 31 Oct. 2020.

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