The Merkaba (also spelled Merkabah) is a sacred geometric form consisting of two interlocking tetrahedra (star tetrahedron) that create a three-dimensional Star of David. In mystical traditions, the Merkaba represents the light body or spiritual vehicle used for interdimensional travel and ascension. The word derives from ancient Egyptian: "Mer" (light), "Ka" (spirit), "Ba" (body) — literally "spirit-body surrounded by light."