itlacahui.

Headword: 
itlacahui.
Principal English Translation: 

to become messed up, harmed, damaged; to be violated (intransitive); to have a stomach ache

Orthographic Variants: 
ytlacaui, itlacaui
IPAspelling: 
ihtɬɑkɑwi
Alonso de Molina: 

itlacaui. (pret. oitlacauh.) corromperse dañarse, o estragarse algo, o empollarse el huevo.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 43r. col. 1. Thanks to Joe Campbell for providing the transcription.

Frances Karttunen: 

(I)HTLACAHU(I) to go wrong, to be ruined or corrupted, to injure oneself, to spoil / corromperse, dañarse, o estragarse algo … o empollarse el huevo (M) This has the same sense as (I)HTLACOĀ used reflexively.
Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 100.

Attestations from sources in English: 

Totlatlalia: itlacavi, inamjc tlanoqujliztli conquaz in quauhtlatlatzin = Stomach Pain: Its remedy is purging. One is to eat pine nuts (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), 155.

itlacahui = to be damaged, harmed (from itlacoa = to harm, damage)
Michel Launey, An Introduction to Classical Nahuatl, translated and adapted by Christopher MacKay (Cambridge: Cambridge University Press, 2011), 198.

aic itlacahuiz = it is never to be violated (The transitive verb is itlacoa, to violate someone or something.)
James Lockhart, personal communication, December 19, 2007.

itlacaui = it becomes damaged (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.

themes: 
Health, Sickness, Wellness, Medicine