The Collaborative International Dictionary of English v.0.48:

Dispossession \Dis`pos*ses"sion\, n. [Cf. F. d['e]possession.]
   1. The act of putting out of possession; the state of being
      dispossessed. --Bp. Hall.
      [1913 Webster]

   2. (Law) The putting out of possession, wrongfully or
      otherwise, of one who is in possession of a freehold, no
      matter in what title; -- called also ouster.
      [1913 Webster]

WordNet (r) 3.0 (2006):

dispossession
    n 1: the expulsion of someone (such as a tenant) from the
         possession of land by process of law [syn: eviction,
         dispossession, legal ouster]
    2: freeing from evil spirits [syn: exorcism, dispossession]

Moby Thesaurus II by Grady Ward, 1.0:

44 Moby Thesaurus words for "dispossession":
   bereavement, cost, damage, dead loss, debit, denial, denudation,
   deprivation, deprivement, despoilment, destruction, detriment,
   disendowment, disherison, disinheritance, dislodgment, disownment,
   disseisin, divestment, eviction, expense, expropriation,
   foreclosure, forfeit, forfeiture, injury, loser, losing,
   losing streak, loss, ouster, ousting, perdition, privation,
   reclaiming, repossessing, repossession, robbery, ruin, sacrifice,
   spoliation, stripping, taking away, total loss