Τηθύς · Tēthys — LSJ
Tethys, wife of Oceanus, nurse of Hera, Il. 14.201, 302; daughter of Uranus and Gaia, mother of the river-gods and Oceanides, Hes. Th. 136, 337, cf. A. Pr. 137 (anap.), Th. 311 (lyr.); Ὠκεανὸν . . καὶ Τηθὺν ἐποίησαν τῆς γενέσεως πατέρας Arist. Metaph. 983b30; taken as type of a very old woman, prob. in Call. Iamb. 1.248 (Hermes 69.174); cf. προτήθυς.
in later writers, the Sea, Lyc. 1069, AP 7.214.6 (Arch.), Nonn. D. 31.187, Orph. A. 335, etc., cf. Porph. ap. Eus. PE 3.11, Suid. [ῡ in disyll. cases, ῠ in trisyll.]