The Collaborative International Dictionary of English v.0.48:

Aubaine \Au`baine"\, n. [F., fr. aubain an alien, fr. L. alibi
   elsewhere.]
   Succession to the goods of a stranger not naturalized.
   --Littr['e].
   [1913 Webster]

   Droit d'aubaine, the right, formerly possessed by the king
      of France, to all the personal property of which an alien
      died possessed. It was abolished in 1819. --Bouvier.
      [1913 Webster]