Where does “egagrópila” come from?

egagrópila (Spanish) comes from Latin aegagropila, from Ancient Greek αἴγαγρος, from Latin pila, from Latin pīlus, from Latin pīlum, from Proto-Italic pistlom, from Proto-Indo-European pis-tlo-, from Proto-Indo-European peys- — to grind, to crush.

egagrópila (Spanish): a food pellet regurgitated by owls and vultures