itepoz temmecayo cahuallo.

(a loanword from Spanish)

itepoz temmecayo cahuallo.
Principal English Translation: 

bridle or bit of a horse (see Molina)
(partly a Spanish loanword, caballo, horse)

Orthographic Variants: 
itepuz temmecayo cauallo. itepuz temmecayo cahuallo, itepuz temmecayo caballo
Alonso de Molina: 

itepuz temmecayo cauallo. freno de cauallo.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 42v. col. 1. Thanks to Joe Campbell for providing the transcription.