brown rat

noun

: 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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Sewer rats are brown rats that live in sewers, and street rats are brown rats that live on the streets. — Rivka Galchen, New Yorker, 12 Feb. 2026 For the first time, a brown rat has been caught on camera actively hunting bats. — Sarah Durn, Popular Science, 30 Oct. 2025 There's a lot of work being done on invasive predators, such as the brown rat. — Alex Ledsom, Forbes.com, 29 Dec. 2025 The recovery follows the removal of black and brown rats that had accidentally arrived on the island as stowaways on ships and shipwrecks. — Moná Thomas, PEOPLE, 2 July 2026 See All Example Sentences for brown rat

Word History

First Known Use

1737, in the meaning defined above

Time Traveler
The first known use of brown rat was in 1737

Rhymes for brown rat

See All Rhymes for brown rat

Browse Nearby Words

brownprint
brown rat
brown recluse spider
See all Nearby Words

Cite this Entry

“Brown rat.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/brown%20rat. Accessed 7 Jul. 2026.

Copy Citation

Kids Definition

brown rat

noun
: the common rat that is found about human dwellings

Medical Definition

brown rat

noun
: 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

Britannica.com: Encyclopedia article about brown rat

Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

Popular in Grammar & Usage

See More

Is that lie 'bald-faced' or 'bold-faced'?

'A' or 'an'? What about before 'h'? An Indefinite Article Guide

Why is '-ed' sometimes pronounced at the end of a word?

Commonly Misspelled Words

How to Use Em Dashes (—), En Dashes (–) , and Hyphens (-)
See More

Popular in Wordplay

See More

14 Phobias You Probably Haven't Heard Of

The Longest Long Words List

One-Word Oxymorons: Bittersweet, Spendthrift, and More

Ten Words Ending with a Silent ‘T’

12 Lovely and Unusual Words for the Natural World
See More

Popular

See More

Is that lie 'bald-faced' or 'bold-faced'?

14 Phobias You Probably Haven't Heard Of

The Longest Long Words List
See More

Games & Quizzes

See All
Play Quordle: Guess all four words in a limited number of tries. Each of your guesses must be a real 5-letter word.
Quordle Can you solve 4 words at once?
Play Blossom: Solve today's spelling word game by finding as many words as you can using just 7 letters. Longer words score more points.
Blossom Pick the best words!
Play Missing Letter: a crossword with a twist. Each of the 25 puzzle words start with a different letter of the alphabet. Which letter is missing?
The Missing Letter A daily crossword with a twist
hangman letters and game
Hangman Lightning Round Figure out which word fits in the blanks.
See All