to throw a staff/rod with the help of a leather strap (see Molina, who gives the example in the first person singular)
Alonso de Molina:
atlacopa nitlamina (pret. atlacopa onitlamin.) tirar vara con amiento. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 8r. col. 1. Thanks to Joe Campbell for providing the transcription.