chachahuatl.

Headword: 
chachahuatl.
Principal English Translation: 

a rodent that is a mammal and similar to a mouse; or, a kind of animal that is similar to a rat (see Molina)

Orthographic Variants: 
chachauatl
Alonso de Molina: 

chachauatl. liron, o cierto animal como rata.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 19r. col. 1. Thanks to Joe Campbell for providing the transcription.