cuentaxtli.

(a loanword from Spanish)

Headword: 
cuentaxtli.
Principal English Translation: 

beads (from the Spanish, cuentas, with the suffix -tli; suggests an early borrowing)

Fr. Bernardino de Sahagún, Florentine Codex: General History of the Things of New Spain; Book 2 -- The Ceremonies, no. 14, Part III, 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, 1951), 122; citing Barry Sell, personal communication.

Orthographic Variants: 
cuenta, cuentas
Alonso de Molina: 

cuentaxtli. cuentas para rezar.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 26r. col. 1. Thanks to Joe Campbell for providing the transcription.

Attestations from sources in English: 

quipiazque çeçeaca cuentastli huey Rosario = each of them will have rosary beads, a big rosary
Fray Alonso de Molina, Nahua Confraternities in Early Colonial Mexico: The 1552 Nahuatl Ordinances of fray Alonso de Molina, OFM, ed. and trans., Barry D. Sell (Berkeley: Academy of American Franciscan History, 2002), 112–113.

The term derives from the prayer that involved rosary beads, and their counting, hence the Spanish term for counts.