nu·​di·​branch ˈnü-də-ˌbraŋk How to pronounce nudibranch (audio)
plural nudibranchs
: any of an order (Nudibranchia) of marine opisthobranch mollusks without a shell in the adult state and without true gills
nudibranch adjective

Illustration of nudibranch

Illustration of nudibranch

Example Sentences

Recent Examples on the Web Notable diners include sea turtles, ocean sunfish, and somewhat distant cousins of the octopus, nudibranchs, which will consume jellies and other cnidarians while somehow keeping their stinging cells in tact so they can be repurposed for the nudibranch's defense. Christie Wilcox, Discover Magazine, 31 Mar. 2017 Best known for: The coral reefs, located to the south of Koh Phangan on the western shore of the Gulf of Thailand, are colorful and packed with a diverse range of marine life which ranges from mighty whale sharks and majestic manta rays to exquisite nudibranch and macro-critters. Stacey Leasca, Travel + Leisure, 1 June 2021 The Glaucus is considered to be a type of pelagic nudibranch that devours bluebottles and stores their stinging agents as defense against predators. Alan Taylor, The Atlantic, 25 Jan. 2023 With over 3,000 different species on record, the nudibranch is an extremely versatile kind of sea slug. Courtney Linder, Popular Mechanics, 17 Aug. 2022 For example, the Hilton’s nudibranch, a predatory sea slug, expanded northward during the Blob, which led to a decline in local nudibranchs. Erica Nielsen, The Conversation, 4 Oct. 2021 The nudibranch, besides using the hydroids for habitat, regularly consume its home colony’s polyps. Sid Perkins, Science | AAAS, 31 Oct. 2017 With their dazzling colors and intricate patterns, nudibranchs are among the world’s most glamorous marine creatures. Brigit Katz, Smithsonian, 4 Nov. 2017 The video from his April 17 dive revealed vibrant sea creatures that have made the chilly northern waters their home—among them, a transparent Arctic jellyfish, a sparkly skeleton shrimp, and a white nudibranch, or soft-bodied mollusk. Hannah Lang, National Geographic, 6 July 2017 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'nudibranch.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


New Latin Nudibranchia, from Latin nudus + Greek branchia gills

First Known Use

1844, in the meaning defined above

Time Traveler
The first known use of nudibranch was in 1844

Dictionary Entries Near nudibranch

Cite this Entry

“Nudibranch.” Dictionary, Merriam-Webster, Accessed 2 Jun. 2023.

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