In Greek mythology, the Meliae or Meliai were nymphs of the ash tree, whose name they shared. They appeared from the drops of blood spilled when Cronus castrated Uranus, according to Hesiod. From the same blood sprang the Erinyes, suggesting perhaps that the ash-tree nymphs represented the Fates in milder guise, and the Giants. From the Meliae sprang the race of mankind of the Age of Bronze.

The Meliae belong to a class of sisterhoods whose nature is to appear collectively and who are invoked in the plural, though genealogical myths, especially in Hesiod, give them individual names, such as Melia, "but these are quite clearly secondary and carry no great weight". The Melia thus singled out is one of these daughters of Oceanus. By her brother the river-god Inachus, she became the mother of Io, Phoroneus, Aegialeus orPhegeus, and Philodice. In other stories, she was the mother of Amycus by Poseidon, as the Olympian representative of Oceanus.

Many species of Fraxinus, the ash trees, exude a sugary substance, which the ancient Greeks called méli, "honey". The species of ash in the mountains of Greece is the Manna-ash. The Meliae were nurses of the infant Zeus in the Cretan cave of Dikte, according to Callimachus, Hymn to Zeus. They fed him honey.

The Meliai were perhaps the same as the honey-nymph nurses of the god Zeus, Ida, and Adrasteia. The manna meli of the ash and the honey of bees were thought to be related and being regarded as an ambrosial food fallen from heaven. In Hesiod's Theogony they were born aside the Erinyes, avengers of the castration of Uranus, and the Gigantes. In Hesiod appear to be the Kourete-protectors of the baby Zeus. As children born of the castration, it would be proper that they are brothers should play a role in the downfall of Cronus, performer of the crime. They were an overly aggressive race who incurred the wrath of Zeus and were ruined in the flood of the Great Deluge.