sea slug

American  

noun

1. a nudibranch.

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sea slug British  

noun

1. any of various shell-less marine gastropod molluscs, esp those of the order Nudibranchia See nudibranch

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sea slug Scientific  

1. Any of various colorful marine gastropods of the suborder Nudibranchia, lacking a shell and gills but having fringelike projections that serve as respiratory organs.

2. Also called nudibranch

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Etymology

Origin of sea slug

First recorded in 1770–80

Example Sentences

See Examples For:

sea slug

According to the team, he "never realized Thecacera sesama was a new species until he consulted the sea slug expert 'Hsini Lin teacher' on Facebook."

From Science Daily ● May 27, 2026

Over the past 20 years, the team has used the institute’s underwater technology to gather more information on the sea slug.

From Los Angeles Times ● Nov. 14, 2024

A new species of sea slug has been discovered in UK waters.

From BBC ● Feb. 29, 2024

“They spend their lives floating on the ocean surface upside-down, and swallow air to help them stay afloat,” says Ángel Valdés, a sea slug specialist at California State Polytechnic University.

From National Geographic ● Feb. 7, 2024

Aplysia, a sea slug that looks as though it couldn’t be good for anything, has been found by neurophysiologists to be filled with truth.

From "The Lives of a Cell" by Lewis Thomas