but, however (adversative conjunction) (see Molina)
Alonso de Molina:
ece. empero, conjunction aduersatiua. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 28r. col. 1. Thanks to Joe Campbell for providing the transcription.