sea cucumber

noun

: any of a class (Holothurioidea) of echinoderms having a tough muscular elongate body with tentacles surrounding the mouth

called also holothurian

Illustration of sea cucumber

Examples of sea cucumber in a Sentence

Recent Examples on the Web

In rare trips to the deep sea, scientists have uncovered sea cucumbers with purple-magenta ombre coloring; yeti crabs with hairy, feather-like claws; octopuses with ears like the Disney character Dumbo; iridescent mollusks; and phantasmic jellyfish. —Amber X. Chen, Smithsonian Magazine, 18 July 2025

There are also benefits to using a natural source such as the sea cucumber, the researchers said. —Paul McClure 10, New Atlas, 10 June 2025

Discoveries like bloody frogs and raw sea cucumbers raise concerns about possible disease transmission, invasive species and violations of international trade and wildlife protection laws. —Anna Commander, MSNBC Newsweek, 26 July 2025

Despite concerns about the limited availability of sea cucumbers, the compound is expected to become a crucial blueprint for future cancer research. —Jack Knudson, Discover Magazine, 10 June 2025

Word History

First Known Use

1841, in the meaning defined above

Kids Definition

sea cucumber

noun

: any of a class of invertebrate sea animals that are echinoderms with a long tough flexible muscular body resembling a cucumber and having tentacles surrounding the mouth at one end