The Grammarphobia Blog

How did the guinea pig get its name?

Q: Where did the term “guinea pig” come from? I hope it wasn’t originally derogatory.

A: We don’t know exactly how the guinea pig got its name, but no ethnic slur was intended.

The guinea pig (or “cavy”), a small rodent of the genus Cavia, originated in South America but is now found in cages – and on laps – throughout the world.

So it isn’t from Guinea (which is the name of both a country and a region in western Africa), and it isn’t a pig.

The Oxford English Dictionary mentions three theories about the origin of this inappropriate name:

(1) The animal was perhaps “thought to resemble the young of the Guinea Hog (Potamochoerus),” which is a river pig found in Guinea.

(2) Back when the phrase “guinea pig” was first recorded, the word “Guinea” was often used to denote some unspecified or unknown faraway land.

(3) The “guinea” here may represent a confusion with Guiana, a region of northeastern South America. This explanation “seems unlikely,” the OED says.

And here’s another suggestion, from the Chambers Dictionary of Etymology:

(4) The little feller was named for the people who brought it to England, “the ‘Guinea-men’ who sailed on ships plying between England, Guinea, and South America, to which the animal is native.” (The ships themselves, usually slavers, were also called “Guinea-men” or “Guineamen.”)

There are other less likely explanations, which I won’t go into and which you can find online. Suffice it to say that the animal’s name is still a mystery.

The phrase “guinea pig” first appeared in print, according to the OED, in 1664, in Henry Power’s book Experimental Philosophy.

Here’s the rather icky quotation, in which Power describes the feeding habits of cheese mites: “You may see them … like so many Ginny-Pigs, munching and chewing the cud.”

In 1774, the novelist, poet, and playwright Oliver Goldsmith described the mouse as “the most timid of all quadrupeds, except the guinea-pig.” (The comment was in a book of juvenile nonfiction.)

Guinea pigs have also been used in scientific research over the centuries, and “guinea pig” is often used to mean one who participates in an experiment.

This sense of the term, which was first recorded in the early 20th century, is still around, though mice and rats have largely replaced guinea pigs in laboratories.

Here’s a typical citation, from H. G. Wells’s Men Like Gods (1923): “And may I ask … the nature of this treatment of yours, these experiments of which we are to be the – guinea pigs, so to speak?”

Since you mention it, the derogatory term “guinea” is American slang dating from the late 19th century. But the word wasn’t originally a slur.

The Random House Historical Dictionary of American Slang notes that as far back as 1748, the term “Guinea Negro” (later shortened to “guinea”) was used to describe a black person of West African origin.

This term survived well into the 19th century, as you can see from this 1887 quotation from the Louisville (Ky.) Courier-Journal: “I am a Guinea negro and I belong to the old-time negroes of Africa. My father was a Guinea negro and my mother was a Guinea.”

In 1890, “guinea” was first used as a contemptuous epithet for an Italian (or occasionally someone of central or southern European origins), according to Random House.

In 1911 it was first used to mean a Hispanic person. It was also used, Random House says, for “a person of Creole or mixed black, white, and Indian ancestry.”

By the way, in case you’re wondering about the “guinea” in English money, I wrote a blog entry last year that explained how the guinea, pound, sovereign, and quid got their names.

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