diving beetle

noun

any of numerous predaceous water beetles of the family Dytiscidae, having the body adapted for swimming.

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British Dictionary definitions for diving beetle

diving beetle

noun

any of the aquatic predatory beetles of the widely distributed family Dytiscidae, characterized by flattened hindlegs adapted for swimming and diving

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