brown rat


Definition of brown rat

: a common domestic rat (Rattus norvegicus) that has been introduced worldwide

called also Norway rat

Examples of brown rat in a Sentence

Recent Examples on the Web The extinct animal is also closely related to a living rat species, sharing around 95 percent of its genome with the Norway brown rat, according to the study. NBC News, 9 Mar. 2022 Seoul spreads among and from the common brown rat—sometimes called a sewer rat, wharf rat, or Norway rat. Beth Mole, Ars Technica, 4 Mar. 2022 Some people speculate that the brown rat saved us from the plague. Sarah Zhang, The Atlantic, 26 Apr. 2021 Pack rats, as well as their cousins the black and brown rats, don’t just collect sticks and seeds. Sadie Witkowski, Smithsonian, 15 Nov. 2019 For comparison purposes, the modern brown rat is less than one foot in length and weighs approximately 8 ounces. Fox News, 15 Feb. 2020 The dominant rat in New York City is the Norway rat, Rattus norvegicus, also known as the brown rat. Charlie Hamilton James, National Geographic, 17 June 2019 Rattus norvegicus - the brown rat - is a destructive force in much of the world, wreaking ecological havoc, contaminating crops, vandalizing property and spreading as many as 35 diseases. Author: Amanda Coletta, Anchorage Daily News, 28 Sep. 2019 Black rats weigh in at 4½ ounces and grow up to 5 to 6 inches long; adult brown rats weigh 9 to 10 ounces and reach up to 16 inches., 27 Aug. 2019 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'brown rat.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of brown rat

1737, in the meaning defined above

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Time Traveler for brown rat

Time Traveler

The first known use of brown rat was in 1737

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Dictionary Entries Near brown rat


brown rat

brown recluse spider

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Statistics for brown rat

Cite this Entry

“Brown rat.” Dictionary, Merriam-Webster, Accessed 4 Jul. 2022.

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More Definitions for brown rat

brown rat


Medical Definition of brown rat

: a common domestic rat of the genus Rattus (R. norvegicus) that has been introduced worldwide

called also Norway rat

More from Merriam-Webster on brown rat Encyclopedia article about brown rat


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