Caxtillantlatolli.

(a loanword from Spanish)

Headword: 
Caxtillantlatolli.
Principal English Translation: 

the Spanish language (attested in modern Nahuatl)

Victoriano de la Cruz Cruz, Facebook posting, June 5, 2014, Nahuatlahtolli page.

Orthographic Variants: 
Caxtillantlahtolli