Caer

1. Irish goddess who, in the story The Dream of Oengus, is seen by Oengus mac ind Og in his dreams. He falls in love with her, but cannot find her, and languishes in the wasting sickness of love, so prevalent in Celtic myths. Driven half mad with desire, he goes to great lenghts to find her, and when he does, sees her in the form of a swan. So, Oengus changes into a swan, and they fly away together.

2. caer (-au, ceyrydd): n.f. wall, castle, citadel. Common element of Welsh placenames; analogous to "chester." In The Chronicles of Narnia, the placename of Cair Paravel is derived from the Welsh word caer. [ Welsh; compare with the Irish cathair and Latin castra ]