In Greek mythology

Greek mythology

Greek mythology is the body of myths and legends belonging to the ancient Greeks, concerning their gods and heroes, the nature of the world, and the origins and significance of their own cult and ritual practices. They were a part of religion in ancient Greece...

, Eunostus or Eunostos was a goddess whose image was set up in mills, and who was believed to keep watch over the just weight of flour.

Promylaia ("the one that stands before/protects the mill") was another name for a goddess of the mills, who was worshipped in the same fashion as Eunostus. Both Eunostus and Promylaia could actually have been mere epithets of Demeter

Demeter

In Greek mythology, Demeter is the goddess of the harvest, who presided over grains, the fertility of the earth, and the seasons . Her common surnames are Sito as the giver of food or corn/grain and Thesmophoros as a mark of the civilized existence of agricultural society...

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