ehuachimalli.

tzinacantopilli, in tepuztlavitolli, in tepuzmitl: yoā no vncan maceoaloc in tepuzquacalalatli, in tepuzvipilli, in tepuzmatlavipilli, in eoachimalli, in tepuchimalli, in quauhchimalli = halberds, crossbows, crossbow, bolts. And also they acquired there iron helmets, iron cuirasses, coats of mail, leather shields, metal shields, wooden shields. (Mexico City, sixteenth century)
James Lockhart, We People Here: Nahuatl Accounts of the Conquest of Mexico, Repertorium Columbianum v. 1 (Los Angeles: UCLA Center for Medieval and Renaissance Studies, 1993), 160.