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 Alpacas aren't the typical animals enlisted for the program, which allows people to cuddle with pets like dogs, cats, bunnies, and guinea pigs to help lower their stress levels and provide other health benefits. Benjamin Vanhoose,, "Therapy Alpacas Visit Seniors During Pandemic: 'Animals Have a Magical Way of Healing'," 30 Apr. 2020 When Dumb Friends League, a private animal shelter in Denver, put out a call for volunteers to foster dogs, cats, bunnies, guinea pigs and even horses, more than 2,200 people signed up. Maria Puente, USA TODAY, "Adoptions, fosters empty shelter cages during COVID-19 crisis, but there will always be homeless pets," 29 Apr. 2020 His willingness to be the guinea pig of sorts paid off on Sunday, as the Fuel’s Tracer composition was better equipped to assist Gamsu. Sean Collins, Dallas News, "5 things we learned about the Dallas Fuel after they earned first win of 2020," 6 Apr. 2020 Into this sky-high hellscape comes Goreng (Ivan Massagué), not a prisoner but a volunteer, who has signed on for six months as a guinea pig in exchange for an accredited diploma. Jason Bailey, New York Times, "‘The Platform’ Review: An Accidentally Timely Political Allegory," 26 Mar. 2020 Adoption fees at the shelter range from $30 for a guinea pig to $130 for a cat to $450 for a puppy. Maria Lovato,, "Scituate Animal Shelter waives adoption fees after donation from Miranda Lambert," 10 July 2019 This isn't the first time the former race-car driver has served as a guinea pig to his wife's DIY beauty projects involving his hair. Megan Decker,, "Bachelor Stars Lauren & Arie Luyendyk Dyed Each Other’s Hair & Look Unrecognizable," 14 Apr. 2020 Researchers have now seen evidence of hidden hearing loss in dead mice, guinea pigs, rats, chinchillas, and nonhuman primates. Popular Science, "Hidden hearing loss is hitting people of all ages. Neuroscientists are still debating why.," 21 Jan. 2020 In Ecuador, people typically cook guinea pigs with salt and serve them with potatoes and peanut sauce. Gonzalo Solano,, "Cone or scoop: Guinea pig ice cream for sale in Ecuador," 4 Oct. 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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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

21 May 2020

Cite this Entry

“Guinea pig.” Dictionary, Merriam-Webster, Accessed 3 Jun. 2020.

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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

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