The Collaborative International Dictionary of English v.0.48:

Disorganize \Dis*or"gan*ize\, v. t. [imp. & p. p.
   Disorganized; p. pr. & vb. n. Disorganizing.] [Pref. dis-
   + organize: cf. F. d['e]sorganiser.]
   To destroy the organic structure or regular system of (a
   government, a society, a party, etc.); to break up (what is
   organized); to throw into utter disorder; to disarrange.
   [1913 Webster]

         Lyford . . . attempted to disorganize the church.
                                                  --Eliot
                                                  (1809).
   [1913 Webster]

WordNet (r) 3.0 (2006):

disorganized
    adj 1: lacking order or methodical arrangement or function; "a
           disorganized enterprise"; "a thousand pages of muddy and
           disorganized prose"; "she was too disorganized to be an
           agreeable roommate" [syn: disorganized, disorganised]
           [ant: organized]