pitzahui.

Headword: 
pitzahui.
Principal English Translation: 

to get thin (See Karttunen)

Orthographic Variants: 
pitzāhui
IPAspelling: 
pitsɑːwi
Frances Karttunen: 

PITZĀHU(I) to get thin / se adelgaza (T) [(4)Tp.119,175]. In a compound with CUAUH T has a short vowel in the second syllable but in the free form T has a long one. M has synonymous pitzaua, which forms its preterit by adding -C. It is apparently the same verb with an idiosyncratic vowel-length variation.
Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 197.