any gastropod mollusk of the order Opisthobranchia, as the sea slugs, sea butterflies, and sea hares, characterized by a vestigial or absent mantle and shell and two pairs of tentacles.
of or relating to the opisthobranches.
- Also o·pis·tho·bran·chi·ate [uh-pis-thuh-brang-kee-it, -eyt]. /əˌpɪs θəˈbræŋ ki ɪt, -ˌeɪt/.
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How to use opisthobranch in a sentence
C, Diblastula of an opisthobranch (Polycera) with elongated blastopore oi.
British Dictionary definitions for opisthobranch
any marine gastropod of the class Opisthobranchia (or Opisthobranchiata), in which the shell is reduced or absent: includes the pteropods, sea hares, and nudibranchs
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012