How the animals came to be thought of as "pigs" is not clear. One thought is that some of the sounds they make reminded people of pigs, for they emit a variety of sounds, some very similar to a pig's squeal. They are built somewhat like a pig, with a large head relative to the body, a stout neck, and a rounded rump with no tail of any consequence; they also spend a large amount of time eating. They can survive fairly well for long periods of time in small quarters, like a 'pig pen', and were thus easily transported on ships to Europe.
The animal's name carries connotations of it being a pig in many languages. The German word for them is Meerschweinchen, literally "little sea pigs" (sailing ships stopping to re-provision in the New World would pick up stores of guinea pigs, which provided an easily transportable source of fresh meat; Meerschwein = porpoise, another food source for sailors). The Welsh term is mochyn cwta ('little pig'), the French Cochon d'Inde (Indian pig); the Dutch used to call it guinees biggetje (Guinean piglet). In Italian the term is either Porcellino d'India (Little Indian Pig) or Cavia Peruviana (Peruvian Cavy). This is not universal; for example, the common Spanish word is conejillo de Indias (Indian bunny rabbit / Indies bunny).
The scientific name of the common species is Cavia porcellus, with porcellus being Latin for "little pig". Cavia is derived from Portuguese çavia (now savia) from the Tupi word sawiya, meaning rat.[citation needed]
The origin of "guinea" in "guinea pig" is even harder to explain. According to the etymology of the entry for "guinea pig" in The American Heritage® Dictionary of the English Language, Fourth Edition, the term guinea pig is "Perhaps [an] alteration (influenced by Guinea, used as a name for any faraway unknown country) of Guiana".[3] One theory is that the animals were brought to Europe by way of Guinea, leading people to think they had originated there. Another theory suggests that "Guinea" in the case of the guinea pig is a corruption of "Guiana", an area in South America. A common misconception is that they were so named because they were sold as the closest thing to a pig one could get for a guinea (an old British coin with a value of 21 shillings, or 1.05 GBP in modern decimal currency). However, evidence does not support this conjecture: for example, the Dutch name refers to the country of Guinea rather than the British coin, and the first guinea pig was described in 1554 by the Swiss naturalist Konrad Gesner more than a hundred years before the first guinea was struck.[citation needed] Others believe guinea is a corruption of the word coney, because guinea pigs were called pig coneys in 1607 [1]; they resemble rabbits, ignoring the ears.

