The Yaqui language belongs to the Uto-Aztecan language family. Yaqui speak a Cahitan language, a group of about 10 mutually-intelligible languages formerly spoken in much of the states of Sonora and Sinaloa. Most of the Cahitan languages are extinct; only the Yaqui and Mayo still speak their language. About 15,000 Yaqui speakers live in Mexico and 1,000 in the U.S.A, mostly Arizona.
The Yaqui call themselves Hiaki or Yoeme, the Yaqui word for person (yoemem or yo’emem meaning “people”). The Yaqui call their homeland Hiakim, from which some say the name “Yaqui” is derived. They may also describe themselves as Hiaki Nation or Pascua Hiaki, meaning “The Easter People”, as most had converted to Catholicism under Jesuit influence in colonial Mexico. Many folk etymologies account for how the Yoeme came to be known as the “Yaqui”.
Yaqui is a tonal language, with a tonal accent on either the first or the second syllable of the word. The syllables which follow the tone are all high.
Read on Wikipedia