Glas Gaibhnenn

Glas Gaibhnenn (Glas Gaivlen;alternate spelling: Gloss Gavlen:pronunciation guide:/glas-gav-e-lan/;) is a prized fabulous cow of bounty (fertility) that yields profuse quantities of milk, and which belonged to semi-mythological characters in Irish oral folktales.

The bovine creature has been described variously as a cow which is "white with green spots" (Mackillop), or "Goibniu's Grey or Brindled (Cow)" (Rhys).

Power listed Glas Gamhain and Bó Bhán "white cow" (associated with Boann) as among names of mythological creatures after which landscape features or bodies of water were often named, while Patricia Monaghan wrote of Glas Ghaibhleann as a goddess often associated with rivers, and that rivers were often seen as embodiments of the goddess Boann.

The folk-tale plot has been made familiar through retellings of Irish mythology, notably by Lady Gregory, but also others where we learn that Cian mounts on a quest to recover the magic cow, has a romantic encounter with Balor's daughter, fathering the child who is to become Lugh. The folktale was stitched together using additional bona fide medieval mythological writings to form a seamless retelling. Two rather different oral versions of the folktale were pieced into one composite for this purpose.

Glas Gaibhnenn reconstructed in normalised Irish: Glas Gaibhnenn. Pronunciation guide: /Glos gov-nan/. Original (phonetic) transcription: Glas Gaivlen; alternate spellings: Gloss Gavlen: (pronunciation guide:/glas-gav-e-lan/). Additional spellings: Glas Gaibhneach, Glas Gamhain, Glas Gamhnach.

O'Donovan thought the second part of the name was a corruption of the possessive case of Goibniu "the smith", as Goibniu is Old Irish, pronounced ˈɡovʲnʲu or Gaibhne (Modern Irish). But the bovine creature's Irish name can literally be broken down to "green, gray, etc." and "calf, yearling", as have been indicated by the Rev. Patrick Power, church historian and writer on topographical names.

Lady Gregory's reworked version can be summarised as follows: Balor of the Strong Blows (or the Evil Eye) learns from his druids that he is fated to be slain by his own grandson. Consequently, he sequesters his only daughter Ethlinn (this name has been normalised to conform with mythology, but she is called Ethnea in the original folktale). Around this time, at a place called Druim na Teine ("the Ridge of the Fire") lived three brothers, Goibniu the smith, Samthainn, and Cian together with the wonderful cow Glas Gaibhnenn. But one day when Cian comes to Goibniu's forge to have his sword wrought, leaving the other brother Samthain in charge of the cow, Balor comes along to trick Samthain into abandoning his guard, and steals away the cow back to his own island across the strait. Cian, seeks help from a druidess (and member of the Tuatha De Danaan) named "Birog of the Mountain" who informs him that the cow could never be recovered while Balor was alive. With a blast of wind she conveys Cian to Balor's tower, and penetrating the prison, allows Cian opportunity for a tryst with Balor's daughter. In the retelling, the focus switches now to the fate of the child Lugh who is born between them, so the eventual fate of the cow remains untold.

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