to become fierce (see Molina), literally, to become beast-like
Orthographic Variants:
tequantilia
Alonso de Molina:
tequantilia. nino. (pret. oninotequantili.) tornarse ohazerse brauo. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 104v. col. 2. Thanks to Joe Campbell for providing the transcription.