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

With cages artfully lining one wall of the room with their owners standing by, fans can pet a guinea pig while looking at the paraphernalia. Caroline Tew,, "You can hold adorable guinea pigs at Fleabag-inspired pop-up cafe in Los Angeles," 7 Aug. 2019 The amount of time [referees] are taking to make decisions means, unfortunately, the women’s game, once again, is a guinea pig. Xavier Harding, Fortune, "Women's World Cup: VAR Instant Replay Tech Has Players and Fans up in Arms," 24 June 2019 The tournament was a guinea pig to a new penalty rule introduced at the beginning of this month which begs the question: is it the officials or the way VAR and a new law has been introduced at this major tournament? Aimee Lewis, CNN, "Women's World Cup: Referees and VAR under the microscope after dramatic weekend in France," 23 June 2019 Fried chicken and fries may be delicious but so is guinea pig. National Geographic, "Here’s why every foodie you know is heading to Peru," 19 July 2019 My younger sister and I were thrilled by the unexpected birth of three baby guinea pigs. Los Angeles Times, "Readers remember the Apollo 11 moon landing, 50 years later," 18 July 2019 The Humane Society has approximately 30 cats, 10 dogs, four guinea pigs, and one rabbit available for adoption currently, according to Hampton. Mary Grace Keller,, "Happy tails: Children learn at Carroll County Humane Society Critter Camp," 15 July 2019 The backyard is full of the bones of our pets, mostly cats, but some gerbils, too, and even one guinea pig. Beth Thames |,, "Bloom where you are planted," 26 June 2019 But that doesn’t excuse the shoddy decision by FIFA and international rules officials to essentially make the World Cup a guinea pig for a rules change. Nancy Armour, USA TODAY, "Opinion: Two weeks in at World Cup, USWNT among winners, while FIFA remains a huge loser," 21 June 2019

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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Statistics for guinea pig

Last Updated

14 Aug 2019

Look-up Popularity

Time Traveler for guinea pig

The first known use of guinea pig was in 1664

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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

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More from Merriam-Webster on guinea pig

Rhyming Dictionary: Words that rhyme with guinea pig

Spanish Central: Translation of guinea pig

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

Comments on guinea pig

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not constant or steady

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