Principal English Translation:
there is; there are; exists; or, to have
Alonso de Molina:
onca. auer algo. vel. ay algo. s. para dar.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 77r. col. 1. Thanks to Joe Campbell for providing the transcription.
Lockhart’s Nahuatl as Written:
there is (i.e. the subject of the verb exists). with a possessed noun subject, to have. in cihuātl oncateh ōme īconēhuān, the woman has two children. on-, cah. 228
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), 228.
Attestations from sources in English:
aço onca anoço atley = perhaps there is something or perhaps there is nothing
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), 96–97.