The Collaborative International Dictionary of English v.0.48:

Estrangement \Es*trange"ment\, n. [Cf. OF. estrangement.]
   The act of estranging, or the state of being estranged;
   alienation.
   [1913 Webster]

         An estrangement from God.                --J. C.
                                                  Shairp.
   [1913 Webster]

         A long estrangement from better things.  --South.
   [1913 Webster]

WordNet (r) 3.0 (2006):

estrangement
    n 1: separation resulting from hostility [syn: alienation,
         estrangement]
    2: the feeling of being alienated from other people [syn:
       alienation, disaffection, estrangement]