tlapachiuhcayo cahuallo.

(a loanword from Spanish)

Headword: 
tlapachiuhcayo cahuallo.
Principal English Translation: 

a horse that is covered with a blanket
(partly a loanword from Spanish, caballo, horse)

Orthographic Variants: 
tlapachiuhcayo cauallo
Alonso de Molina: 

tlapachiuhcayo cauallo. cauallo emmantado.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 130v. col. 1. Thanks to Joe Campbell for providing the transcription.