The Collaborative International Dictionary of English v.0.48:

Haunt \Haunt\ (h[aum]nt; 277), v. t. [imp. & p. p. Haunted; p.
   pr. & vb. n. Haunting.] [F. hanter; of uncertain origin,
   perh. from an assumed LL. ambitare to go about, fr. L. ambire
   (see Ambition); or cf. Icel. heimta to demand, regain, akin
   to heim home (see Home). [root]36.]
   1. To frequent; to resort to frequently; to visit
      pertinaciously or intrusively; to intrude upon.
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            You wrong me, sir, thus still to haunt my house.
                                                  --Shak.
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            Those cares that haunt the court and town. --Swift.
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   2. To inhabit or frequent as a specter; to visit as a ghost
      or apparition; -- said of spirits or ghosts, especially of
      dead people; as, the murdered man haunts the house where
      he died.
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            Foul spirits haunt my resting place.  --Fairfax.
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   3. To practice; to devote one's self to. [Obs.]
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            That other merchandise that men haunt with fraud . .
            . is cursed.                          --Chaucer.
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            Leave honest pleasure, and haunt no good pastime.
                                                  --Ascham.
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   4. To accustom; to habituate. [Obs.]
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            Haunt thyself to pity.                --Wyclif.
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The Collaborative International Dictionary of English v.0.48:

Haunted \Haunt"ed\, a.
   Inhabited by, or subject to the visits of, apparitions;
   frequented by a ghost.
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         All houses wherein men have lived and died
         Are haunted houses.                      --Longfellow.
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WordNet (r) 3.0 (2006):

haunted
    adj 1: 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, preoccupied, taken
           up(p)]
    2: showing emotional affliction or disquiet; "her expression
       became progressively more haunted"
    3: inhabited by or as if by apparitions; "a haunted house"

Moby Thesaurus II by Grady Ward, 1.0:

26 Moby Thesaurus words for "haunted":
   beset, dogged, fretted, ghost-haunted, ghost-ridden, harassed,
   harried, hounded, mindful, nagged, obsessed, persecuted, plagued,
   possessed, rankled, remembering, specter-haunted, spirit-haunted,
   spooked, spooky, tormented, unable to forget, vexed, worried,
   worried sick, worried stiff