Fomori

The Fomorians (Old Irish: Fomoire, Modern Irish: Fomhóraigh) are a supernatural race in Irish mythology. They are often portrayed as hostile and monstrous beings who come from the sea or underground. Later, they were portrayed as giants and sea raiders. They are enemies of Ireland's first settlers and opponents of the Tuatha Dé Danann, the other supernatural race in Irish mythology. However, their relationship with the Tuath Dé is complex and some of their members intermarry and have children. The Fomorians have thus been likened to the jötnar of Norse mythology.

The Fomorians seem to have been gods who represent the harmful or destructive powers of nature; personifications of chaos, darkness, death, blight and drought. The Tuath Dé, in contrast, seem to represent the gods of growth and civilization. It has also been suggested that the Fomorians derive from an older group of gods who were displaced by a newer group.

In Old and Middle Irish, the race is usually called the Fomoire or Fomoiri (plural), and an individual member is called a Fomoir (singular). In Middle Irish, they are also called the Fomóraiġ (plural) and a Fomórach (singular). This is spelt Fomhóraigh (plural) and Fomhórach (singular) in Modern Irish. In English, they are often called the Fomorians, Fomori or Fomors.

The etymology of the name is debated. The first part is now generally agreed to be the Old Irish fo, meaning under, below, lower, beneath, nether, etc. The meaning of the second part is unclear. One suggestion is that it comes from the Old Irish mur (sea), and that the name thus means something like "the undersea ones". This was the interpretation offered by some medieval Irish writers. Another suggestion is that it comes from mór (great/big) and means something like "the great under(world) ones", "the under(world) giants" or "the nether giants". A third suggestion, which has more support among scholars, is that it comes from a hypothetical Old Irish term for a demon or phantom, found in the name of The Morrígan and cognate with the archaic English word "mare" (which survives in "nightmare"). The name would thus mean something like "under(world) demons" or "nether demons". Building on this, Marie-Louise Sjoestedt interprets the name as meaning "inferior" or "latent demons", saying the Fomorians are "like the powers of chaos, ever latent and hostile to cosmic order".

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