to stalk, spy or to lean out to see what is happening (see Molina)
Orthographic Variants:
nauallachia
Alonso de Molina:
nauallachia. ni. (pret. oninauallachix.) asechar mirando, o asomandose. 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.