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guinea pig

noun
Updated on: 22 May 2018
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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

See guinea pig defined for English-language learners

See guinea pig defined for kids

Examples of guinea pig in a Sentence

  1. He volunteered to act as a guinea pig in the experiment.

Recent Examples of guinea pig from the Web

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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GUINEA PIG Defined for English Language Learners

guinea pig

noun

Definition of guinea pig for English Language Learners

  • : a small animal that is often kept as a pet

  • : a person or thing used for testing something

GUINEA PIG Defined for Kids

guinea pig

noun

Definition of guinea pig for Students

: 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

Medical Dictionary

guinea pig

noun 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

Learn More about guinea pig

  1. See words that rhyme with guinea pig Spanish Central: Translation of guinea pig Nglish: Translation of guinea pig for Spanish speakers Britannica.com: Encyclopedia article about guinea pig

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guinea pig

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Examples: guinea pig in a Sentence