According to a quotation from Hesiod's lost work Eoiae or Catalogue of Women, preserved in the De Thematibus of Constantine Porphyrogenitus, Thyia (Ancient Greek: Θυία) was the daughter of Deucalion and Pyrrha and mother of Magnes and Makednos (the claimed ancestor of the Macedonians) by Zeus.
In the Delphic tradition, Thyia was also the naiad of a spring on Mount Parnassos in Phocis (central Greece), daughter of the river god Cephissus. Her shrine was the site for the gathering of the Thyiades (women who celebrated in the orgies of the god Dionysos). She was said to have been the first to sacrifice to Dionysus, and to celebrate orgies in his honour. Hence, the Attic women, who every year went to Mount Parnassus to celebrate the Dionysiac orgies with the Delphian Thyiades, received themselves the name of Thyades or Thyiades.
She was said to have been loved by Apollo and bore him Delphos, the eponymous founder of town Delphi, beside the oracular shrine. She was also closely associated with the prophetic Castalian Spring, from which she was sometimes said to have been born. Thyia was also related to Castalia, the nymph of the spring; Melaena, an alternative mother for Delphos; and the Corycian nymphs, naiades of the springs of the holy Corycian Cave.
Thyia was a name derived from the Ancient Greek verb θύω meaning "perfume" or "sacrifice". The name was applied to a type of fragrant tree called a Thuja.