to hit the mark or be right in doing something, or to pass someone, or to encounter with them (see Molina)
Alonso de Molina:
ipan niauh (pret. ipan onia.) atinar o acertar en algo, o passar por donde otro esta, o encontrar con el. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 41v. col. 2. Thanks to Joe Campbell for providing the transcription.