Source : Webster's Revised Unabridged Dictionary (1913)

Preoccupy \Pre*oc"cu*py\, v. t. [imp. & p. p. {Preoccupied}
   (-p[=i]d); p. pr. & vb. n. {Preoccupying}.] [Cf. F.
   pr['e]occuper. See {Preoccupate}, {Occupy}.]
   1. To take possession of before another; as, to preoccupy a
      country not before held.

   2. To prepossess; to engage, occupy, or engross the attention
      of, beforehand; hence, to prejudice.

            I Think it more respectful to the reader to leave
            something to reflections than to preoccupy his
            judgment.                             --Arbuthnot.

Source : WordNet®

preoccupied
     adj 1: deeply absorbed in thought; "as distant and bemused as a
            professor listening to the prattling of his freshman
            class"; "lost in thought"; "a preoccupied frown" [syn:
             {bemused}, {deep in thought(p)}, {lost(p)}]
     2: having or showing excessive or compulsive concern with
        something; "became more and more haunted by the stupid
        riddle"; "was absolutely obsessed with the girl"; "got no
        help from his wife who was preoccupied with the children";
        "he was taken up in worry for the old woman" [syn: {haunted},
         {obsessed}, {taken up(p)}]

preoccupy
     v 1: engage or engross the interest or attention of beforehand or
          occupy urgently or obsessively; "His work preoccupies
          him"; "The matter preoccupies her completley--she cannot
          think of anything else"
     2: occupy or take possession of beforehand or before another or
        appropriate for use in advance; "the army preoccupied the
        hills"
     [also: {preoccupied}]

preoccupied
     See {preoccupy}