In Ancient Egypt, hieroglyphic sign indicating infinity. Being a circle, or a ring of rope knotted at the bottom, it had no end, therefore its meaning. The shen could be shown encircling the sun, then representing the eternity of the universe as well as protection. The shen would develop into the ouroboros sign, which is the snake biting its own tail. The sign as often associated with Horus and Nekhbet, the first then shown as a falcon, the second shown as a vulture. During the Middle Kingdom, the shen was frequently used as amulets.
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