to winnow wheat, or something similar (see Molina)
IPAspelling:
ekɑketsɑ
Alonso de Molina:
ecaquetza. nitla. (pret. onitlaecaquetz.) auentar trigo, o cosa semejante. 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.