-oa.

Headword: 
-oa.
Principal English Translation: 

an ending that makes a noun into a verb

Orthographic Variants: 
-ohua
Lockhart’s Nahuatl as Written: 

Ending of many of the verbs of Class 3. Class 3 derivational suffix that creates verbs from nouns meaning to put the thing named by the noun into action. also creates loan verbs by being added to the Sp. infinitive. pret. -oh.
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), 227.

Attestations from sources in English: 

chiaoa = it becomes grease-stained; the root is the noun relating to the chia seeds, from which oil was derived (central Mexico, sixteenth century)
Fr. Bernardino de Sahagún, Florentine Codex: General History of the Things of New Spain; Book 10 -- The People, No. 14, Part 11, 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, 1961), 97.

iztaleoa = it becomes pale (central Mexico, sixteenth century)
Fr. Bernardino de Sahagún, Florentine Codex: General History of the Things of New Spain; Book 10 -- The People, No. 14, Part 11, 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, 1961), 97.