The Collaborative International Dictionary of English v.0.48:

Alien \Al"ien\, a. [OF. alien, L. alienus, fr. alius another;
   properly, therefore, belonging to another. See Else.]
   1. Not belonging to the same country, land, or government, or
      to the citizens or subjects thereof; foreign; as, alien
      subjects, enemies, property, shores.
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   2. Wholly different in nature; foreign; adverse; inconsistent
      (with); incongruous; -- followed by from or sometimes by
      to; as, principles alien from our religion.
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            An alien sound of melancholy.         --Wordsworth.
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   Alien enemy (Law), one who owes allegiance to a government
      at war with ours. --Abbott.
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