Linguists recognize 16 separate languages spoken in Oaxaca today. Experts identify each of them with one of five language families. North American language family names are conventionally derived by combining the names of the northernmost and southernmost languages of the group. Thus, Otomanguean, Oaxaca’s most widespread language family, derives its label from Otomi, spoken northwest of Mexico City, and Mangue, spoken in southeast Mexico. All of Oaxaca’s native language speakers occupy pretty much the same territories that they did at the time of the conquest. The Otomanguean, by location, moving generally west to east, are: Amusgo, Chatino, Trique, Mixtec, Chocho, Ixcatec, Popoluca, Cuicatec, Mazatec, Chinantec, and Zapotec. A language pair of eastern Oaxaca, Mixe (MEE-shay) and Zoque (SOH-kay), probably distantly related to Mayan dialects, are often lumped into a second family, the Mixe-Zoque family. Three other languages are the only representatives of their respective families. Nahuatl (the language of the Aztecs) of the Uto-Aztecan family; Chontal, of the Hokan-Coahuiltecan family; and Huave, of its own family, Huave.
Understanding in Oaxaca is further complicated by a proliferation of dialects. Mixtec speakers from Jamiltepec [1], on the Pacific coast, for example, do not generally comprehend the Mixtec dialect of a town, such as Tlaxiaco, across half a dozen ridges 100 miles away. The same is true for Oaxaca’s other major languages—Zapotec, Mazatec, Chinantec, and Mixe—and to a lesser degree, for the minor languages.
Few nonindigenous people, whether foreigners or Mexican, have made the intense effort required to speak and understand a Oaxacan native language. All of the Otomanguean languages, like the Chinese dialects, are tonal. This means that a given word takes on different meanings depending upon the pitch—low, high, rising, or falling—with which it is enunciated. Consequently, in big market towns, Spanish is often the lingua franca of buying and selling. Nevertheless, at many country markets, aware visitors notice many people, usually older folks, who speak no Spanish at all.
Please take note that the Spanish names for the Zapotec, Mixtec, Mazatec, and Chinantec languages are Zapoteco, Mixteco, Mazateco, and Chinanteco, while the respective home territories of each group are the Zapoteca, Mixteca, Mazateca, and Chinantla.
Links:
[1] http://www.moon.com/destinations/oaxaca/pacific-resorts/-mixtec-coast/santiago-jamiltepec