a noblewoman, a woman of very high stature, such as a queen or a marquise
Orthographic Variants:
ciua tlahtoani, cihua tlatoani
Alonso de Molina:
ciua tlatoani. señora principal, assi como reynamarquesa. &c Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 22v. col. 2. Thanks to Joe Campbell for providing the transcription.