TETHYS was the Titan goddess of the sources fresh water which nourished the earth. She was the wife of Okeanos, the earth-encircling, fresh-water stream, and the mother of the Potamoi (Rivers), Okeanides (Springs, Streams & Fountains) and Nephelai (Clouds). Tethys was imagined feeding her children’s streams by drawing water from Okeanos through subterranean aquifers. Her name was derived from the Greek word têthê, “the nurse” or “grandmother.”
In Greek vase painting Tethys appears as an attributeless woman in the company of Eileithyia, the goddess of childbirth, and her fish-tailed husband Okeanos. In mosaic art she appears with a small pair of wings decorating her brow, probably in her role as the mother of rain-couds.
Tethys was likely identified with the Titanis Eurynome, one-time Queen of Heaven, who was cast into the Ocean-stream along with her husband Ophion by Kronos. She was probably also connected with the Protogenos Thesis (Mother Creation) who appears in the Orphic cosmogony. Tethys was later represented by poets as the sea personified, and so equated with Thalassa.