Literally, "the old women." Also called Phorcydes. They first appear in Hesiod (Theog.) and are by him declared to be daughters of the sea-god, Phoreys, by his sister, Ceto, and sisters of the three Gorgons. They are beautiful, well-dressed, and white of hair from birth. In Æschylus (Prom. Vinc.) they are described as monsters, swan-shaped, and possessing in common but one eye and one tooth, which neither the sun nor the moon had ever shone upon, and which they borrowed from one another as occasion demanded. Some of the poets make them guardians of the Gorgons. Their names are: Pephredo, Enyo, and Dino. The Graiae have been thought to symbolize the clouds, the transferable eye and tooth representing the flash of the lightning and its rapid interchange from one cloud to another. For the connection of the Phoreydes, or Graiae, with the Perseus myth, see Gorgon.
A look at the past . . .. Arch Ophthalmol. 1998;116(12):1624. doi:10.1001/archopht.116.12.1624