to form a cup, referring to a tree or the like (see Molina)
Alonso de Molina:
momalacayotia. (pret. omomalacayoti) hazer copa el arbol o cosa semejante. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 58v. col. 2. Thanks to Joe Campbell for providing the transcription.