The Collaborative International Dictionary of English v.0.48:

Uphold \Up*hold"\, v. t.
   1. To hold up; to lift on high; to elevate.
      [1913 Webster]

            The mournful train with groans, and hands upheld.
            Besought his pity.                    --Dryden.
      [1913 Webster]

   2. To keep erect; to support; to sustain; to keep from
      falling; to maintain.
      [1913 Webster]

            Honor shall uphold the humble in spirit. --Prov.
                                                  xxix 3.
      [1913 Webster]

            Faulconbridge,
            In spite of spite, alone upholds the day. --Shak.
      [1913 Webster]

   3. To aid by approval or encouragement; to countenance; as,
      to uphold a person in wrongdoing.
      [1913 Webster]

WordNet (r) 3.0 (2006):

uphold
    v 1: keep or maintain in unaltered condition; cause to remain or
         last; "preserve the peace in the family"; "continue the
         family tradition"; "Carry on the old traditions" [syn:
         continue, uphold, carry on, bear on, preserve]
         [ant: cease, discontinue, give up, lay off, quit,
         stop]
    2: stand up for; stick up for; of causes, principles, or ideals
    3: support against an opponent; "The appellate court upheld the
       verdict" [syn: uphold, maintain]

Moby Thesaurus II by Grady Ward, 1.0:

176 Moby Thesaurus words for "uphold":
   OK, accept, admire, advocate, affirm, afford support, aid,
   allege in support, answer, approve, approve of, argue for, assert,
   assist, attest, authenticate, back, back up, backstop, bear,
   bear out, bear up, bless, bolster, bolster up, boost, brace, buoy,
   buoy up, buttress, carry, cast up, certify, champion,
   circumstantiate, confirm, conserve, contend for, copyright,
   corroborate, countenance, counter, cradle, crutch, cushion, defend,
   document, elevate, embrace, endorse, erect, escalate, espouse,
   esteem, favor, finance, float, float high, fortify, fund,
   give support, guard, heave, heft, heighten, heist, help, hike,
   hoick, hoist, hold, hold up, hold with, jerk up, justify, keep,
   keep afloat, keep alive, keep in countenance, keep intact,
   keep inviolate, keep safe, keep up, knock up, lend support,
   levitate, lift, lift up, lob, loft, mainstay, maintain,
   make a plea, not destroy, not endanger, not expend, not use up,
   not waste, patent, perk up, pick up, pillow, plead for, preserve,
   probate, promote, prop, prop up, protect, prove, raise, raise up,
   ratify, rear, rear up, rebut, refute, register, reinforce, reply,
   respect, respond, ride high, riposte, rise, sanction, save,
   say in defense, set up, shore, shore up, shoulder, side with, sky,
   spare, speak for, speak up for, stand by, stand up for, stay,
   stick up, stick up for, strengthen, subsidize, substantiate,
   subvention, subventionize, support, sustain, take kindly to,
   take up, think well of, throw up, underbrace, undergird, underlie,
   underpin, underset, up, upbear, upbuoy, upcast, upheave, uphoist,
   upkeep, uplift, upraise, uprear, upthrow, urge reasons for,
   validate, verify, view with favor, vindicate, waft, warrant