Isthmus Zapotec, one of at least six known varieties of Zapotec, claims the largest number of speakers in the Zapotecean family. It is spoken in Oaxacam in Mexico's Isthmus of Tehuantepec, and in the state's capital city, Oaxaca de Juarez. This is the first dictionary of Isthmus Zapotec to be published in English. In addition to over 5, 000 entries -- with etymological notes given when entry words derive from Spanish -- the dictionary contains detailed yet concise sections covering spelling and pronunciation, as well as the major points of Isthmus Zapotec grammar.