Dana (we also find the spelling Danu), in Irish Celtic mythology is the primordial goddess of the Tuatha Dé Danann, the "people of the goddess Dana", that is to say the gods of the Celts before the Christianization of the island. In Cormac's Glossary (Sanas Cormaic, 10th century manuscript of Bishop Cormac of Cashel) she is also called Ana and Anu. She is the mother of Dagda and Lir. She would be at the origin of the installation of her people in Ireland, while they lived in the four islands in the north of the World. Its equivalent in Welsh Celtic mythology is Dôn.
She is a pan-Celtic goddess. The root of the theonym is very present in European topography, especially rivers such as the Danube (in Latin Danavius), the Dniester, the Dnieper, etc. this indicates that this goddess was worshiped throughout the Celtic world and probably by all Indo-Europeans. There is in Brahmanic mythology a deity named Danu who fathered a race of giants, the Danavas.
The meaning of the name could be "donor", "benefactor" (in India, the Dânapati are the donors of Buddhist monasteries and dâna means the gift), which makes her a goddess of fertility and prosperity. Among the Celts, the redistribution of wealth was the primary quality of the royal function.
In the Irish typonymy, her name is associated with two hills "the Paps", located not far from Killarney, which have the shape of a pair of breasts, they are in Gaelic Dé Chich Anann (Ana's breasts).