WordNet (r) 3.0 (2006):

disassociation
    n 1: the state of being unconnected in memory or imagination; "I
         could not think of him in disassociation from his wife"
         [ant: association]
    2: a state in which some integrated part of a person's life
       becomes separated from the rest of the personality and
       functions independently [syn: dissociation,
       disassociation]

Moby Thesaurus II by Grady Ward, 1.0:

43 Moby Thesaurus words for "disassociation":
   abstraction, alienation, detachment, disarticulation,
   disconnectedness, disconnection, discontinuity, discreteness,
   disengagement, disjointing, disjunction, disjuncture, dislocation,
   dissociation, disunion, division, divorce, divorcement,
   immateriality, impertinence, inapplicability, inappositeness,
   incoherence, inconnection, inconsequence, independence, irrelation,
   irrelevance, isolation, luxation, parting, partition, removal,
   segmentation, separateness, separation, separatism, subdivision,
   subtraction, unconnectedness, unrelatedness, withdrawal, zoning