to fall into a ravine, a hole, or a well (see Molina)
Orthographic Variants:
atlacomulhuia
Alonso de Molina:
atlacomulhuia. nin. (pret. oninatlacomulhui.) abarrancarse, caer en hoyo o pozo. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 8r. col. 1. Thanks to Joe Campbell for providing the transcription.