Principal English Translation:
was going to do something (but it didn't happen) (conditional suffix)
Horacio Carochi / English:
-zquia = ending of the "conditional" tense
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), 516, and see 112-15 and 112 n2.
Lockhart’s Nahuatl as Written:
ending of the tense called conditional, which more often expresses that something was going to happen but didn't. pl. -zquiah.
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), 242.
Attestations from sources in Spanish:
hualamelauhque ycha jues gobernador don Francisco Ruiz ça nima quilpisquia yhua mochi quicuilizquia yn iahuihuan yn icha quicaltentzacque = se dirigieron a la casa del juez gobernador don Francisco Ruíz; de inmediato lo iban a atar y le iban a tomar todas las llaves; en su casa lo dejaron encerrado (Tlaxcala, 1662–1692)
Juan Buenaventura Zapata y Mendoza, Historia cronológica de la Noble Ciudad de Tlaxcala, transcripción paleográfica, traducción, presentación y notas por Luis Reyes García y Andrea Martínez Baracs (Tlaxcala y México: Universidad Autónoma de Tlaxcala, Secretaría de Extensión Universitaria y Difusión Cultural, y Centro de Investigaciones y Estudios Superiores en Antropología Social, 1995), 452–453.