What does the living horus mean?
The phrase, "The Living Horus" was used by Egyptian pharaohs who believed themselves to be an incarnation of the God Horus on Earth. In death, the pharaoh is associated with Osiris - god of the Underworld or Afterlife and the father of the God Horus. It is the god Osiris who grants the pharaoh everlasting life and the spirit of the deceased pharaoh is then associated with the constellation of Orion.
Osiris and Horus are the same deity in different manifestations: Horus represents the sun at dawn while Osiris is the sun at sunset when it disappears below the horizon. So, Osiris dies and is resurrected: to live again as Horus.
It's like when people used to say: "The King is dead! Long live the King!" The death of one pharaoh is swiftly followed by the ascension to the throne of his successor. When a pharaoh died, joining Osiris, the new pharaoh becomes the "Living Horus". Does that help?