nudibranch

American  

[noo-duh-brangk, nyoo-] / ˈnu dəˌbræŋk, ˈnyu- /

noun

1. a shell-less, marine snail of the suborder Nudibranchia, having external, often branched respiratory appendages on the back and sides.

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nudibranch British  

/ ˈnjuːdɪˌbræŋk /

noun

1. Also called: sea slug.  any marine gastropod of the order Nudibranchia, characterized by a shell-less, often beautifully coloured, body bearing external gills and other appendages

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nudibranch Scientific  

/ no̅o̅′də-brăngk′ /

1. See sea slug

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Etymology

Origin of nudibranch

1835–45; < French nudibranche, equivalent to nudi- nudi- + branche gill (< Latin branchia branchia )

Example Sentences

The tiny nudibranch measures less than three millimeters in length and was first spotted in 2019 by lead author Ho-Yeung Chan during a recreational dive.

From Science Daily • May 27, 2026

When Anna Sagatov, an underwater cinematographer, goes on her usual night dives off La Jolla Shores in San Diego, she’s used to spotting the “occasional octopus, nudibranch and horn shark.”

From New York Times • May 9, 2024

Enrico Somogyi won Compact, with a photo of a nudibranch sea slug with a emperor shrimp on its head, in Tulamben, on the north-east coast of Bali, Indonesia.

From BBC • Feb. 19, 2024

This gorgeous little nudibranch of just 2.3 inches long is packed with surprises.

From National Geographic • Feb. 7, 2024

This beautiful nudibranch was first found near Laguna by Miss M. Cate, not far from Dana's point in 1916.

From Journal of Entomology and Zoology Volume Eleven, Number Two, June 1919 by Various