The Collaborative International Dictionary of English v.0.48:

Reserve \Re*serve"\ (r?-z?rv"), v. t. [imp. & p. p. Reserved.
   (z?rvd");p. pr. & vb. n. Reserving.] [F. r['e]server, L.
   reservare, reservatum; pref. re- re- + servare to keep. See
   Serve.]
   1. To keep back; to retain; not to deliver, make over, or
      disclose. "I have reserved to myself nothing." --Shak.
      [1913 Webster]

   2. Hence, to keep in store for future or special use; to
      withhold from present use for another purpose or time; to
      keep; to retain; to make a reservation[7]. --Gen. xxvii.
      35.

   Note: In cases where one person or party makes a request to
         an agent that some accommodation (such as a hotel room
         or place at a restaurant) be kept (reserved) for their
         use at a particular time, the word reserve applies both
         to the action of the person making the request, and to
         the action of the agent who takes the approproriate
         action (such as a notation in a book of reservations)
         to be certain that the accommodation is available at
         that time.
         [1913 Webster +PJC]

               Hast thou seen the treasures of the hail, which I
               have reserved against the time of trouble? --Job
                                                  xxxviii.
                                                  22,23.
         [1913 Webster]

               Reserve your kind looks and language for private
               hours.                             --Swift.
         [1913 Webster]

   3. To make an exception of; to except. [R.]
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Reserved \Re*served"\ (-z?rvd"), a.
   1. Kept for future or special use, or for an exigency; as,
      reserved troops; a reserved seat in a theater.
      [1913 Webster]

   2. Restrained from freedom in words or actions; backward, or
      cautious, in communicating one's thoughts and feelings;
      not free or frank.
      [1913 Webster]

            To all obliging, yet reserved to all. --Walsh.
      [1913 Webster]

            Nothing reserved or sullen was to see. --Dryden.
      [1913 Webster] -- Re*serv"ed*ly (r?-z?rv"?d-l?), adv. --
      Re*serv"ed*ness, n.
      [1913 Webster]

WordNet (r) 3.0 (2006):

reserved
    adj 1: set aside for the use of a particular person or party
           [ant: unreserved]
    2: marked by self-restraint and reticence; "was habitually
       reserved in speech, withholding her opinion"-Victoria
       Sackville-West [ant: unreserved]

Moby Thesaurus II by Grady Ward, 1.0:

120 Moby Thesaurus words for "reserved":
   Olympian, Spartan, abbreviated, abridged, aloof, antisocial,
   aposiopestic, backward, bashful, blank, brief, brusque,
   ceremonious, chilled, chilly, clipped, close, close-lipped,
   close-tongued, closemouthed, cold, compact, compendious,
   compressed, concise, condensed, conserved, constrained, contracted,
   controlled, conventional, cool, crisp, curt, cut, demure, detached,
   diffident, dignified, discreet, distant, docked, elliptic,
   epigrammatic, expressionless, forbidding, formal, frigid, frosty,
   gnomic, guarded, held, held back, held in reserve, ice-cold, icy,
   impassive, impersonal, inaccessible, incommunicable, introverted,
   kept, laconic, modest, modified, noncommittal, offish, pithy,
   pointed, poker-faced, preserved, prim, pruned, put by, quiet,
   remote, removed, repressed, restrained, retained, reticent,
   retiring, rigid, saved, sedate, sententious, short,
   short and sweet, shortened, shrinking, shy, silent, spare,
   standoff, standoffish, strait-laced, subdued, succinct, summary,
   suppressed, synopsized, taciturn, terse, tight, tight-lipped,
   tights, to the point, truncated, unaffable, unapproachable,
   uncommunicative, uncongenial, undemonstrative, unemotional,
   unexpansive, ungenial, unresponsive, unsocial, withdrawn,
   withheld