barrel sponge

noun

: any of various large, usually cylindrical sponges (genus Xestospongia of the class Demospongiae) found especially on tropical coral reefs

I pass over the largest, healthiest barrel sponge I've ever seen—it seems plausible that I could fit inside it …

—Scott Edler, Washington Post, 21 Oct. 2012

Word History

First Known Use

1979, in the meaning defined above

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