nahuac.

Headword: 
nahuac.
Principal English Translation: 

with me; or, a pair, such as a pair of trees (see Molina); this is a postposition or suffix often found on place names

Orthographic Variants: 
nauac
IPAspelling: 
nɑːwɑk
Alonso de Molina: 

nauac. no. pardemi, o comigo.
nauac quauh. parde los arboles. &c.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 063r. col. 2. Thanks to Joe Campbell for providing the transcription.

Attestations from sources in Spanish: 

nauac quauh. par de los arboles. &c.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 063r. col. 2. Thanks to Joe Campbell for providing the transcription.