The Collaborative International Dictionary of English v.0.48:

Surmount \Sur*mount"\, v. t. [imp. & p. p. Surmounted; p. pr.
   & vb. n. Surmounting.] [OE. sourmounten, OF. surmonter,
   sormonter, F. surmonter; sur over + monter to mount. See
   Sur-, and Mount, v. i.]
   1. To rise above; to be higher than; to overtop.
      [1913 Webster]

            The mountains of Olympus, Athos, and Atlas,
            overreach and surmount all winds and clouds. --Sir
                                                  W. Raleigh.
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   2. To conquer; to overcome; as, to surmount difficulties or
      obstacles. --Macaulay.
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   3. To surpass; to exceed. --Spenser.
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            What surmounts the reach
            Of human sense I shall delineate.     --Milton.
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   Syn: To conquer; overcome; vanquish; subdue; surpass; exceed.
        [1913 Webster]

WordNet (r) 3.0 (2006):

surmount
    v 1: get on top of; deal with successfully; "He overcame his
         shyness" [syn: overcome, get over, subdue,
         surmount, master]
    2: be on top of; "The scarf surmounted the gown"
    3: reach the highest point of; "We scaled the Mont Blanc" [syn:
       scale, surmount]
    4: be or do something to a greater degree; "her performance
       surpasses that of any other student I know"; "She outdoes all
       other athletes"; "This exceeds all my expectations"; "This
       car outperforms all others in its class" [syn: surpass,
       outstrip, outmatch, outgo, exceed, outdo,
       surmount, outperform]

Moby Thesaurus II by Grady Ward, 1.0:

80 Moby Thesaurus words for "surmount":
   beat, best, bestraddle, bestride, better, cap, clamber, clamber up,
   clear, climax, climb, climb over, climb up, command, conquer,
   consummate, crest, crown, culminate, deck, defeat, dominate, down,
   escalade, finish, floor, frost, head, hurdle, ice, leap, lick,
   look down upon, master, mount, negotiate, outdo, outstrip, outtop,
   over, overarch, overcome, overleap, overlook, overmaster,
   overmatch, overpower, overset, overshadow, overthrow, overtop,
   overturn, peak, prevail over, ramp, rise above, scale,
   scale the heights, scrabble up, scramble up, send flying, shin,
   shin up, shinny, silence, struggle up, surpass, terminate, throw,
   tip, top, top off, tower above, tower over, trip, trip up,
   triumph over, upclimb, upset, vault