Few place-names have been used to refer to more distinct places than “Guinea.” Four countries now share the name, three in western Africa (Guinea, Guinea-Bissau, and Equatorial Guinea), and one in the western Pacific (Papua New Guinea). Historically, several other places were referenced by the name as well. The Wikipedia disambiguation page lists thirteen “countries” called “Guinea,” in one form or another, including the former Dutch Guinea and German Guinea in West Africa. The same article counts seven additional regions called “Guinea,” including one in Gloucester County, Virginia, USA.
The origin of the term is uncertain. It entered English and other European languages by way of the Portuguese word Guiné, applied by fifteenth-century mariners to the African coast south of the Senegal River. How the term entered Portuguese is unknown. Some have linked it to various Berber words for dark-skinned people, others to the major commercial city of Djenné, located far inland on the Niger River. A third theory holds that “Guinea” comes from the medieval kingdom (or empire) of Ghana, located in modern Mali and Mauritania.
In the eighteenth century, European geographers applied the term “Guinea” broadly to the West African coast, although the exact zone so labeled varied. In Herman Moll’s 1736 map posted here, Guinea does not include the areas that would later be called Portuguese Guinea (now Guinea-Bissau) and Spanish Guinea (now Equatorial Guinea). The early gold trade in this region is reflected in Moll’s map, in which the Gold Coast figures as a prominent sub-division of Guinea. As this area had long been the main source of gold for Europe and the Mediterranean region, British gold coins minted between 1663 and 1813 were called “guineas,” eventually valued at one pound plus one shilling. (To this day, payments at British livestock auctions and horse races are often figured in hypothetical “guineas,” each of which is worth 1.05 pounds.) It has been suggested the use of the term “Guinea” to refer to an area in Gloucester County, Virginia dates to the Revolutionary War, when the local swamps attracted deserting Hessian mercenaries who had been paid in guineas. Although the Wikipedia judges this etymology “incorrect,” it does not supply any alternatives.
The designation of “New Guinea” for the massive island north of Australia dates to 1545, when it was bestowed by the Spanish mariner Yñigo Ortiz de Retez on the basis of the indigenous inhabitants’ physical resemblance to the people of Africa’s Guinea coast. Today the more local term “Papua” is often preferred, with the landmass as a whole sometimes called “Papua Island.” “Papua” is also of uncertain origin, although most sources link it to the Malay term papuah, meaning “frizzled,” evidently referring to the hair texture of the island’s inhabitants. Both “Papua” and “New Guinea” are thus foreign terms that refer to the physical characteristics of the islanders. But both terms have also been indigenized: the official name of the country that covers the eastern half of the island is, in Tok Pisin (Melanesian Pidgin English), Independen Stet bilong Papua Niugini (or, in English, the “Independent State of Papua New Guinea”).
And if that were not complicated enough, “Guinea” is occasionally confused with Guyana (Guiana), a term referencing the northeastern coast of South America. The two words not only sound similar, but they exhibit a parallel geographical structure: both refer to coastal strips that were formerly divided among European powers: Guyana historically encompassed British Guyana (Guyana), Dutch Guiana (Suriname), French Guiana, and Portuguese Guiana (Amapá state of Brazil). The two terms are not etymologically related, as “Guyana” probably stems from a local word meaning “land of many waters.” Confusion between the two, however, may have given rise to the term “guinea pig.” The Guinea pig is a South American rodent with no connection to Africa. Ties to Guyana, however, are tenuous, as the animal originated in the Andes. A more plausible explanation stems from the fact that the rodent was “first brought back to Britain aboard Guinea-men, ships that plied the triangle trade between England, Guinea, and South America.”
The domesticated guineafowl, on the other hand, is of West African origin. But it too has been involved with place-name confusion and substitution. According to one theory, guineafowl were first called “turkeys” in Britain, owing to the fact that they were introduced to the country in the 1500s by “Turkey merchants” who traded with the Ottoman Empire. The first English colonists in New England subsequently confused the large native fowl with the African bird, calling it “turkey” as well. The mix-up extends to scientific nomenclature. According to the Wikipedia, “The word meleagris, Greek for guineafowl, is also shared in the scientific names of the two species, although for the guineafowl it is the species name, whereas for the turkey, it is the name of the genus and (in an altered state) the family.”
As a final note, “Guinea” has also been applied pejoratively to Americans of Italian descent. According to first definition in the Urban Dictionary, “Guinea” is “the most vile racial slur that can be used against an Italian-American. Refers to the Guinea Coast of Africa; using this slur is a very offensive way of implying that Italian-Americans are non-whites…” Actually, the origin of this derogatory usage remains uncertain. According to a theory propounded in the WikiAnswers discussion page, the word goes back to British guinea coins: “the early Italians, seeking jobs & ways to get money, would walk around saying, “Ginny, Ginny, which at the time … was an English form of money…”