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rock borer

British  

noun

  1. any of various sea creatures that bore into rock, such as some sea urchins, sponges, annelid worms, barnacles, isopods, and molluscs

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Example Sentences

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It is a rock borer, and can bore into very hard rock.

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