something turned over; e.g., a vessel (perhaps like a bowl or cup) that has been turned upside down (see Molina)
Alonso de Molina:
tlaixtlapachmantli. lo mesmo es que tlaixtlapachcuepalli. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 123r. col. 2. Thanks to Joe Campbell for providing the transcription.