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 In 2016, Purdue University announced an income-share agreement program as a guinea pig experiment in which students could get money for college in exchange for a cut of their future earnings. Wired, 13 Aug. 2022 While the 1-year-old guinea pig may not have flaming locks of auburn hair, this brunette beauty has no intention of stealing your man. The Republic, The Arizona Republic, 13 Aug. 2022 Other big names behind the mic include Keanu Reeves (Batman), Olivia Wilde (Lois Lane), Jameela Jamil (Wonder Woman), Marc Maron (Lex Luthor), and Kate McKinnon as Lulu, an evil hairless guinea pig. Lester Fabian Brathwaite,, 1 Aug. 2022 In a video posted on Instagram, the light brown guinea pig runs back and forth to dunk the 4.4 cm spheres in a tiny hoop. Asha C. Gilbert, USA TODAY, 3 June 2022 The pity party can't last too long, because a guinea pig who once belonged to Lex Luthor, Lulu (Kate McKinnon, completely unleashed), acquires orange kryptonite, giving her extraordinary powers. Brian Lowry, CNN, 28 July 2022 Jacob Hopkins’ path to becoming a human guinea pig wasn’t particularly fraught. Melissa Healy, Los Angeles Times, 30 June 2022 The small but mighty spacecraft will be the guinea pig for part of NASA’s Artemis program which seeks to place Gateway, a human outpost, in this orbit. Arianna Johnson, Forbes, 28 June 2022 The family went zip lining through a cloud forest, ate guinea pig, and cruised around the Galapagos. Siobhan Reid, Travel + Leisure, 5 June 2022 See More

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.

First Known Use of guinea pig

1664, in the meaning defined at sense 1

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Time Traveler for guinea pig

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The first known use of guinea pig was in 1664

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Dictionary Entries Near guinea pig

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guinea pig

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Last Updated

16 Aug 2022

Cite this Entry

“Guinea pig.” Dictionary, Merriam-Webster, Accessed 17 Aug. 2022.

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More Definitions for guinea pig

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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