pitzini.

Headword: 
pitzini.
Principal English Translation: 

to burst (intransitive); e.g. for the egg to crack open (see Molina, Karttunen, and Sahagún)

IPAspelling: 
pitsiːni
Alonso de Molina: 

pitzini. (pret. opitzin.) quebrarse el hueuo, machucarse la fruta, o quebrarse el ojo, y abrirse o rebentar el encordio o cosa semejante.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 82v. col. 1. Thanks to Joe Campbell for providing the transcription.

Frances Karttunen: 

PITZĪN(I) for something to burst / quebrarse el huevo, machucarse la fruta, o quebrarse el ojo, o reventar el encodio o cosa semejante (M), se exprime (T) [(1)Tp.174|.
Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 198.

Attestations from sources in English: 

pitzini = it bursts open (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.