cleaner fish

noun

: any of several small fish that clean larger fish of parasites and dead tissue

especially : cleaner wrasse

So-called cleaner fish are among the best-known examples of mutualism in nature. These small fish eat parasites off the skin of larger fish, and it's a win-win situation—the small fish gets food and protection from predators while the larger one stays clean and healthy.

—Henry Fountain, New York Times, 28 Apr. 2009

Word History

First Known Use

1958, in the meaning defined above

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