The Collaborative International Dictionary of English v.0.48:

Withdraw \With*draw"\ (w[i^][th]*dr[add]"), v. t. [imp.
   Withdrew (-dr[udd]"); p. p. Withdrawn (-dr[add]n"); p.
   pr. & vb. n. Withdrawing.] [With against + draw.]
   1. To take back or away, as what has been bestowed or
      enjoyed; to draw back; to cause to move away or retire;
      as, to withdraw aid, favor, capital, or the like.
      [1913 Webster]

            Impossible it is that God should withdraw his
            presence from anything.               --Hooker.
      [1913 Webster]

   2. To take back; to recall or retract; as, to withdraw false
      charges.
      [1913 Webster]

WordNet (r) 3.0 (2006):

withdrawn
    adj 1: withdrawn from society; seeking solitude; "lived an
           unsocial reclusive life" [syn: recluse, reclusive,
           withdrawn]
    2: tending to reserve or introspection; "a quiet indrawn man"
       [syn: indrawn, withdrawn]

Moby Thesaurus II by Grady Ward, 1.0:

144 Moby Thesaurus words for "withdrawn":
   Laodicean, Olympian, alienated, alone, aloof, anonymous, apart,
   apathetic, aseptic, backward, bashful, benumbed, blah, blank,
   blase, bored, careless, casual, chilled, chilly, closet, cold,
   comatose, companionless, constrained, cool, desensitized, detached,
   discreet, disinterested, distant, dull, exclusive, expressionless,
   forbidding, friendless, frigid, frosty, guarded, heartless,
   hebetudinous, heedless, homeless, hopeless, icy, impassive,
   impersonal, in a backwater, in a stupor, inaccessible, incognito,
   incurious, indifferent, inmost, innermost, insociable, insouciant,
   insular, interior, intimate, introverted, inward, isolated,
   kithless, languid, lethargic, listless, lone, lonely, lonesome,
   mindless, modest, nonchalant, numb, numbed, offish, out-of-the-way,
   out-of-the-world, passive, personal, phlegmatic, pluckless,
   private, privy, quarantined, regardless, remote, removed,
   repressed, reserved, resigned, restrained, reticent, retired,
   retiring, rootless, secluded, seclusive, segregated, separate,
   separated, sequestered, shrinking, shut off, single-handed, slack,
   sluggish, solitary, solo, soporific, spiritless, spunkless,
   standoff, standoffish, stoic, stolid, stupefied, subdued, supine,
   suppressed, torpid, unabetted, unaccompanied, unaffable, unaided,
   unapproachable, unassisted, unattended, uncaring, uncompanionable,
   unconcerned, uncongenial, undemonstrative, unescorted, unexpansive,
   unfrequented, ungenial, uninquiring, uninterested, uninvolved,
   unmindful, unseconded, unsupported, unvisited