Ayida-Weddo (Ayida Wedo) is the rainbow-serpent lwa of Haitian Vodou, the wife and complement of Damballa, the great white serpent whose slow, encircling movement is felt as the foundation of the world. She belongs, with him, to the Rada rite, the family of cool, benevolent, ancient spirits of West African (especially Dahomean) origin, and her home tradition reaches back to the serpent divinities of Dahomey, where the rainbow-snake is an image of the covenant between sky and earth.
Together the two serpents encircle the cosmos: Damballa the white snake below and about the waters of the earth, Ayida-Weddo the rainbow arching above, and between them they hold the world in a single embracing coil, a figure of wholeness, fertility and cosmic harmony. She is associated with the rainbow, with rain and wind and water, with the union of the waters above and the waters below, and with fertility and the continuance of life. Like Damballa she is a spirit of purity and peace, honoured with white things and served with reverence; where he is the father-serpent she is the mother-serpent, and the couple express in Vodou the completeness that comes of the two together. Vodou is a living faith, and Ayida-Weddo is among its gentlest and most revered spirits, the rainbow that arcs across the sky after rain, the serpent-wife who with her husband binds the world into one.