any of various heteropterous insects adapted to living in the water or on its surface, esp any of the family Belostomatidae (giant water bugs), of North America, India, and southern Africa, which have flattened hairy legs
water bug in American English
1.
any of various hemipteran insects that live in fresh waters, including the backswimmers and the water boatmen
2. US, Loosely
Croton bug
Examples of 'water bug' in a sentence
water bug
Skimming like a water bug, he'd barely made a dent in sleep.