a polyphonic duo; or a duo of organ music (?) (see Molina)
Orthographic Variants:
moncauia cuicatl
Alonso de Molina:
moncauia cuicatl. duo de canto de organo. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 059r. col. 2. Thanks to Joe Campbell for providing the transcription.