guinea pig


Definition of guinea pig

1 : a small stout-bodied short-eared tailless domesticated rodent (Cavia porcellus) of South American origin often kept as a pet and widely used in biological research

called also cavy

2 : a subject of research, experimentation, or testing

Examples of guinea pig in a Sentence

He volunteered to act as a guinea pig in the experiment.
Recent Examples on the Web That bedding you bought online for your child’s guinea pig will come in a bag that’s wrapped in paper and shipped in a box. Greg Petro, Forbes, 7 May 2021 Officers responded to a report of a guinea pig running loose in the park in the 100 block of W. Golden Lake Road. Star Tribune, 1 May 2021 Keeho's older sister, on the other hand, brought him into the world of makeup by employing him as her guinea pig for testing out new looks. Devon Abelman, Allure, 20 Apr. 2021 The Wright family in New York went through a difficult ordeal after bringing home a third guinea pig last spring. Lorraine Allen, Good Housekeeping, 22 Mar. 2021 This 4-year-old guinea pig is as sweet as a Georgia peach and cuter than a button but unfortunately has found her way to the Arizona Humane Society nonetheless. The Arizona Republic, 12 Mar. 2021 Their pets include a cat, Squeaky; a rescue dog from South Carolina named Maezie; a guinea pig named Lily; and a cockatiel, Henry. Lara Bricker, USA TODAY, 28 Dec. 2020 The other initial guinea pig was Sara Luchian, the company’s director of passenger experience. Rob Verger, Popular Science, 11 Nov. 2020 This is Mocha, a smooth-haired guinea pig who loves lettuce and fresh fruit and responds to the different ringtones on owner’s Christine Winters' phone. cleveland, 26 Oct. 2020

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

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First Known Use of guinea pig

1664, in the meaning defined at sense 1

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Time Traveler for guinea pig

Time Traveler

The first known use of guinea pig was in 1664

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Statistics for guinea pig

Last Updated

12 May 2021

Cite this Entry

“Guinea pig.” Dictionary, Merriam-Webster, Accessed 14 Jun. 2021.

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More Definitions for guinea pig

guinea pig


English Language Learners Definition of guinea pig

: a small animal that is often kept as a pet
: a person or thing used for testing something

guinea pig


Kids Definition of guinea pig

: a small stocky South American animal that is a rodent with short ears and a very short tail and is often kept as a pet

guinea pig

guin·​ea pig | \ ˈgin-ē-ˌ How to pronounce guinea pig (audio) \

Medical Definition of guinea pig

: a small stout-bodied short-eared nearly tailless domesticated rodent of the genus Cavia (C. cobaya) often kept as a pet and widely used in biological research

called also cavy

More from Merriam-Webster on guinea pig

Nglish: Translation of guinea pig for Spanish Speakers Encyclopedia article about guinea pig


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