The ouroboros or uroboros (/ˌjʊərəˈbɒrəs/; /ˌʊərəˈbɒrəs/) is an ancient symbol depicting a serpent or dragon eating its own tail. The ouroboros entered Western tradition via ancient Egyptian iconography and the Greek magical tradition. It was adopted as a symbol in Gnosticism and Hermeticism and most notably in alchemy.
The ouroboros is often interpreted as a symbol for eternal cyclic renewal or a cycle of life, death and rebirth; In Gnosticism, a serpent biting its tail symbolized eternity and the soul of the world.[ The Gnostic Pistis Sophia (c. 400 CE) describes the ouroboros as a twelve-part dragon surrounding the world with its tail in its mouth.