Definition of nudibranch
: any of an order (Nudibranchia) of marine opisthobranch mollusks without a shell in the adult state and without true gills
Origin of nudibranch
New Latin Nudibranchia, from Latin nudus + Greek branchia gills
First Known Use: 1844
Learn More about nudibranch
Britannica.com: Encyclopedia article about "nudibranch"
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