Merkabah, also spelled Merkaba, is the divine light vehicle allegedly used by ascended masters to connect with and reach those in tune with the higher realms.
“Mer” means Light. “Ka” means Spirit. “Ba” means Body. Mer-Ka-Ba means the spirit/body surrounded by counter-rotating fields of light, (wheels within wheels), spirals of energy as in DNA, which transports spirit/body from one dimension to another.
In modern esoteric teachings, it is taught that the MerKaBa is an interdimensional vehicle consisting of two equally sized, interlocked tetrahedra of light with a common center, where one tetrahedron points up and the other down.