a high ground to spy or to observe (can also be used a means for communication) (see Molina)
IPAspelling:
neiːʃtiːloːjɑːn
Alonso de Molina:
neixtiloyan. lugar alto para atalayar. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 66v. col. 1. Thanks to Joe Campbell for providing the transcription.