a strong spirit, one that is brave and spirited (see Molina)
Orthographic Variants:
yollo uapaualiztli
Alonso de Molina:
yollo uapaualiztli. animosidad tal. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 41r. col. 1. Thanks to Joe Campbell for providing the transcription.