a royal seat, an indigenous ruler's throne, etc. (see Molina)
Orthographic Variants:
tlahtoca icpalli
Alonso de Molina:
tlatoca icpalli. silla real, o cosa semejante. s. trono. &c. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 140v. col. 1. Thanks to Joe Campbell for providing the transcription.