zo.

Headword: 
zo.
Principal English Translation: 

to be bleeding

IPAspelling: 
soː
Alonso de Molina: 

zo. nino. (pret. oninozoc). sangrarse.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 24v. col. 2. Thanks to Joe Campbell for providing the transcription.

Frances Karttunen: 

ZŌ vrefl, vt; pret: ZŌC to pierce oneself; to draw blood by piercing someone / sangrarse (M), punzar y sangrar (C), pinchar, sangrar a alguien (S).
Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 347.