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

It is filled with photos and videos of young animals like puppies and kittens, and also pandas, monkeys, guinea pigs, etc. Kaitlin Menza, Marie Claire, "8 Totally Free Pick-Me-Ups Our Editors Swear By," 19 July 2017 This 3 Airport Hacks To view this video please enable JavaScript, and consider upgrading to a web browser that : 0%: 0% TL;DR: Don't be the guinea pig with new budget airlines. Bridget Hallinan, Condé Nast Traveler, "Woman Arrives at Airport for Flight That 'Doesn't Exist'," 20 Sep. 2018 Japanese doctors used the prisoners as guinea pigs, infecting them with anthrax and plague. James M. Scott, WSJ, "Five Best: James M. Scott," 8 Nov. 2018 Now Windows Insiders get to act as the guinea pigs for the rest of us. Brad Chacos, PCWorld, "How Windows 10 will prevent updates from randomly rebooting your PC: machine learning," 26 July 2018 Scialla volunteered himself—and his apartment—as the company's first guinea pig. Stephanie Wu, Town & Country, "The Mastermind Behind Leo DiCaprio's $10M Eco Retreat," 8 May 2014 Santa Monica, known to being more open to working with companies like Uber and Lyft, is the unofficial guinea pig for the company's door-to-door experiments. Meredith Carey, Condé Nast Traveler, "Curious About Lyft's Plans for the Future? Look to Santa Monica," 20 Sep. 2018 And although elephants and rock hyraxes (which resemble guinea pigs) do not have descending testicles, RXFP2 and INSL3 are still intact in both. New York Times, "The Evolutionary Origin of Descending Testicles," 29 June 2018 And some of us out here are just the guinea pigs for that. Mackenzie Schmidt,, "Nicole Curtis Says She Will Keep Fighting for Her Family: ‘Sometimes the Storm Clears the Path’," 10 July 2018

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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Last Updated

30 Jan 2019

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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 \

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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