that is, the rainy, the name of a class of nymphs whose number, names, and descent, are described in various ways by the ancients.
Thales mentioned two, and Euripides three Hyades and Eustathius gives the names of three, viz. Ambrosia, Eudora, and Aesyle. Hyginus on the other hand, mentions Idothea, Althaea, and Adraste and Diodorus has Philia, Coronis, and Cleis.
Other poets again knew four, and Hesiod five, viz. Phaesyle, Coronis, Cleeia, Phaeote, and Eudora.
But the common number of the Hyades is seven, as they appear in the constellation which bears their name, viz., Ambrosia, Eudora, Pedile, Coronis, Polyxo, Phyto, and Thyene, or Dione. Pherecydes, the logographer, who mentioned only six, called them the Dodonaean nymphs, and the nurses appointed by Zeus to bring up Dionysus.
In this capacity they are also called the Nysaean nymphs.
When Lycurgus threatened the safety of Dionysus and his companions, the Hyades, with the exception of Ambrosia, fled with the infant god to Thetis or to Thebes, where they entrusted him to Ino (or Juno), and Zeus showed them his gratitude for having saved his son by placing them among the stars.
Previous to their being thus honoured, they had been old, but been made young again by Medeia at the request of Dionysus. As nymphs of Dodona they were said, in some traditions, to have brought up Zeus.
The story which made them .the daughters of Atlas relates that their number was twelve or fifteen, and that at first five of them were placed among the stars as Hyades, and the seven (or ten) others afterwards under the name of Pleiades, to reward them for the sisterly love they had evinced after the death of their brother Hyas, who had been killed in Libya by a wild beast.
Their name, Hyades, is derived by the ancients from their father, Hyas, or from Hyes, a mystic surname of Dionysus and according to others from their position in the heavens, where they formed a figure resembling the Greek letter T. The Romans, who derived it from a pig, translated the name by Suculae but the most natural derivation is from to rain, as the constellation of the Hyades, when rising simultaneously with the sun, announced rainy and stormy weather.