achto.

Headword: 
achto.
Principal English Translation: 

first, firstly (see Molina et al)

IPAspelling: 
ɑtʃto
Alonso de Molina: 

Achto. primero, o primerante. aduer.
Achtopa. lo mesmo es que achto. aduer.
Alonso de Molina, Vocabulario en lengua mexicana y castellana, 1571 (www.idiez.org.mx), f. 2r.

Frances Karttunen: 

ACHTO first / primero, o primeramente (M)
Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 3.

Horacio Carochi / English: 

achto = first
Horacio Carochi, S.J., Grammar of the Mexican language with an explanation of its adverbs (1645), translated and edited with commentary by James Lockhart, UCLA Latin American Studies Volume 89 (Stanford: Stanford University Press, UCLA Latin American Center Publications, 2001), 360–61, 381 n5, 496.

Lockhart’s Nahuatl as Written: 

achto = first
James Lockhart, Nahuatl as Written: Lessons in Older Written Nahuatl, with Copious Examples and Texts (Stanford: Stanford University Press and UCLA Latin American Studies, 2001), 210.

Attestations from sources in English: 

nican tlami yn intlahtol huehuetque yn achto christianosme catca yn achto momachtianime pipiltin catca = here ends the account of the ancient ones who were the first Christians, the nobleman who were the first neophytes (central Mexico, early seventeenth century)
Codex Chimalpahin: Society and Politics in Mexico Tenochtitlan, Tlatelolco, Culhuacan, and Other Nahuatl Altepetl in Central Mexico; The Nahuatl and Spanish Annals and Accounts Collected and Recorded by don Domingo de San Antón Muñón Chimalpahin Quauhtlehuanitzin, eds. and transl. Arthur J. O. Anderson and Susan Schroeder (Norman: University of Oklahoma Press, 1997), vol. 1, 62–63.

yn achto = at first
Robert Haskett and Stephanie Wood's notes from Nahuatl sessions with James Lockhart and subsequent research.yn iiacac vitz xochitl ic tlamanalo, aiac achto qujnecuj, intlacamo achto ic tlamanaz = It was the first flowers to appear which were thus given as offerings. None might breathe the scent without first providing an offering. (16th century, Mexico City)
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), 55.