Yopoch.

this was the name of the person who would be arrayed in the likeness of Huitzilopochli during ceremonies in the deity's honor; he would wear this gear for a year, fast, and dance; his is referred to as the ixiptla of Huitzilopochtli

(central Mexico, sixteenth century)
Fr. Bernardino de Sahagún, Florentine Codex: General History of the Things of New Spain; Book 3 -- The Origin of the Gods, Part IV, eds. and transl. Arthur J. O. Anderson and Charles E. Dibble (Santa Fe and Salt Lake City: School of American Research and the University of Utah, 1978), 7.