azo.

Headword: 
azo.
Principal English Translation: 

perhaps, maybe, by chance (see Molina); see also our separate entry for zo in contemporary Eastern Huastecan Nahuatl, which means "or"

Orthographic Variants: 
aço, ahzo, azoc
IPAspelling: 
ɑhso
Alonso de Molina: 

Aço. porventura, o quiça. Aduerbio.
Aço cana. quiça en alguna parte o lugar.
Alonso de Molina, Vocabulario en lengua mexicana y castellana, 1571, (www.idiez.org.mx), f. 2v.

azoza. quiza porventura. s. vendra. &c.
azozan. quiza.
azozan ic tiquimmocniuhti? quiza. s. heziste algo para tomar los por amigos?
azozannen. quiza sin prouecho o sin razon. s. heziste algo.
azozan nouian. quiza en todas, o por todas partes.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 2v. col. 2. Thanks to Joe Campbell for providing the transcription.

azozan te oticcuic. quiza lo tomaste de tu auctoridad, o lo hurtaste.
azozan ticmauizcauh. quiza lo dexaste por temor.
azoquema. quiza es assi.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 3r. col. 1. Thanks to Joe Campbell for providing the transcription.

Frances Karttunen: 

AHZO perhaps / por ventura, o quizá (M)
Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 9.

Horacio Carochi / English: 

àço = perhaps, or, either, question word, whether
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), 410–11, 464–65 especially n5, 497.

Lockhart’s Nahuatl as Written: 

"aço, like cuix, is more or lest 'prhaps.' When it introduces dependent clauses, it often translates as 'whether' or 'if.'" (p. 37);
ahço, aço = perhaps (p. 210)
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).

Attestations from sources in English: 

Azoc uel achic, azoc cemiluitl. = Perhaps a few minutes, perhaps even a day.
Thelma D. Sullivan, "Nahuatl Proverbs, Conundrums, and Metaphors, Collected by Sahagún," Estudios de Cultura Náhuatl 4 (1963), 164–165.

Azo + ic, can be combined to form acic (notes from James Lockhart's seminar) to mean "perhaps because of it" (different from acic, he or she arrived).

Attestations from sources in Spanish: 

ynic patlahuac y aço onpohuali at noço nepa amo huel niguilnamigui = tendrá cuarenta brazas de ancho o más que no me acuerdo bien (Tlaxcala, 1609)
Vidas y bienes olvidados: Testamentos en náhuatl y castellano del siglo XVII, vol. 3, Teresa Rojas Rabiela, et al, eds. (México: CIESAS, 2002), 60–61.