doppelgaumnger

from The Collaborative International Dictionary of English v.0.48
Doppelgaumnger \Dop"pel*g[aum]ng`er\, n. [G.]
   A spiritual or ghostly double or counterpart; esp., an
   apparitional double of a living person; a cowalker.
   [Webster 1913 Suppl.]
    

[email protected]