- a short-eared, tailless rodent of the genus Cavia, usually white, black, and tawny, commonly regarded as the domesticated form of one of the South American wild species of cavy: often used in scientific experiments or kept as a pet.
- Informal. the subject of any sort of experiment.
Origin of guinea pig
Examples from the Web for guinea pig
Well, my opinion of him is that he is merely a guinea-pig—you know what that is?A Woman Intervenes
This is a quite peculiar group, characteristic for the blood of the guinea-pig.Histology of the Blood
The capybara is classed with the Cavidae or guinea-pig tribe.The Western World
You will have to take the guinea-pig box out of your room under the eaves.True to His Home
The guinea-pig is not a pig, nor does it come from Guinea (see p. 51).The Romance of Words (4th ed.)
- a domesticated cavy, probably descended from Cavia porcellus, commonly kept as a pet and used in scientific experiments
- a person or thing used for experimentation
Word Origin and History for guinea pig
1660s, native to South America and perhaps so called either because it was first brought back to Britain aboard Guinea-men, ships that plied the triangle trade between England, Guinea, and South America [Barnhart, Klein]; or from confusion of Guinea (q.v.) with the South American region of Guyana (but OED is against this). In the extended sense of "one subjected to an experiment" it is first recorded 1920, because they were commonly used in vivisection experiments.
- Any of various small, short-eared domesticated rodents of the genus Cavia, having variously colored hair and no visible tail. They are widely kept as pets and often used as experimental animals.