Guinea pig


      • A small rodent
        To refer to an actual guinea pig, a common household pet or laboratory animal. This meaning is often used in a literal sense, such as when talking about pet ownership or scientific experiments involving these animals.

      • A test subject
        To refer to a person or group who is used to test a new product, idea, or concept. This is often used in a figurative sense, such as when discussing market research or trying out a new strategy.

      • A person who is easily taken advantage of
        To refer to someone who is naive or gullible and can easily be manipulated or used by others. This is often used in a negative sense, implying that the person is being used for someone else's benefit.

      • A term used for food
        To refer to a dish or food item that is not commonly eaten or is considered strange or exotic. This is often used in a playful or humorous way, such as when trying a new and unusual dish at a restaurant.

    Examples of Guinea pig

    • Alice's boss asked her to be the guinea pig for their new marketing campaign.

      In this example, "guinea pig" is being used as a metaphor to describe someone who is being used as a test subject for a new product, program, or idea. It's often used to describe someone who is being asked to take on a new, untested role or responsibility, with the understanding that it may not work out perfectly. Alice's boss is asking her to be the first person to try out this marketing campaign and see how it performs, in order to determine whether it's effective or needs to be revised.

    • John's friend suggested that he try out a new restaurant before they both went, to be the guinea pig and make sure it wasn't a total disaster.

      In this example, "guinea pig" is being used in a similar way, but in this case, it's being used to describe someone who is being asked to test out a new experience or situation before a larger group or audience experiences it. John's friend is asking him to be the first person to try out the new restaurant, to ensure that it's not a complete failure and that they won't both have a terrible dining experience.

    • Sarah's company is planning to implement a new policy, and they're asking Sarah to be the guinea pig and test it out before they roll it out company-wide.

      Here, "guinea pig" is being used to describe someone who is being asked to try out a new policy or procedure before it's implemented more broadly. Sarah's company is asking her to be the first person to follow the new policy, to see how it works in practice and whether it needs to be adjusted or refined before everyone else starts using it.

    • The school was trying out a new curriculum for their science program, and my daughter was one of the guinea pigs selected to participate.

      In this example, "guinea pig" is being used to describe a student who is being asked to participate in a new educational program or curriculum before it's rolled out to the whole school. The school is asking my daughter to take part in the new science program, in order to test out the curriculum, materials, and teaching strategy before it's introduced to other students. My daughter is essentially serving as a test subject, in order to help the school determine whether the new curriculum is effective and worth implementing more broadly.


    The idiom "guinea pig" can have a variety of meanings, but they all stem from the original meaning of the small rodent. It can refer to an actual guinea pig, a test subject, a gullible person, or even a type of food. In all cases, the idiom is used to describe something or someone who is being experimented on or used in some way.

    Origin of "Guinea pig"

    The origin of the idiom "guinea pig" can be traced back to the 16th century when Spanish explorers brought guinea pigs from South America to Europe. These animals were initially used for food, but later became popular as pets due to their gentle nature and ease of care.

    In the 19th century, guinea pigs were also commonly used in scientific experiments, thus giving rise to the meaning of a test subject. This usage can be seen in George Bernard Shaw's play, "Pygmalion," where the character of Eliza Doolittle is referred to as a "guinea pig" by Professor Higgins.

    The negative connotation of the idiom, referring to a gullible person, may have originated from the idea that guinea pigs are easily manipulated and used for scientific purposes. This meaning can also be seen in the phrase "being a guinea pig" which refers to someone being subjected to experimentation or testing.

    Overall, the idiom "guinea pig" has evolved from its literal meaning to have a variety of figurative meanings, all linked to the animal's history and usage in different contexts.