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definitions

brown rat

noun
  1. Norway rat.

Origin of brown rat

First recorded in 1820–30
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for brown rat

brown rat

noun
  1. a common brownish rat, Rattus norvegicus : a serious pest in all parts of the worldAlso called: Norway rat
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