water rat Meaning, Definition & Usage

  1. noun a person who enjoys being in or on the water
    water dog.
  2. noun common large Eurasian vole
    Arvicola amphibius; water vole.
  3. noun any of various amphibious rats

WordNet

Wa"ter rat`
Definitions
  1. (Zoöl.) (a) The water vole. See under Vole. (b) The muskrat. (c) The beaver rat. See under Beaver.
  2. A thief on the water; a pirate.

Webster 1913