ixtozoa. n. (pret. onixtozo.) velar o trasnochar. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 48v. col. 1. Thanks to Joe Campbell for providing the transcription.
Frances Karttunen:
ĪXTŌZOĀ to keep vigil, to stay awake through the night / pasa toda la noche en vela (C) ((I)Bf.7v,(1)Cf.97r). See ĪX-TLI, TŌZOĀ. Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 122.