The Collaborative International Dictionary of English v.0.48:

Remarkable \Re*mark"a*ble\ (-?-b'l), a. [F. remarquable.]
   Worthy of being remarked or noticed; noticeable; conspicuous;
   hence, uncommon; extraordinary.
   [1913 Webster]

         'T is remarkable, that they
         Talk most who have the least to say.     --Prior.
   [1913 Webster]

         There is nothing left remarlable
         Beneath the visiting moon.               --Shak.
   [1913 Webster]

   Syn: Observable; noticeable; extraordinary; unusual; rare;
        strange; wonderful; notable; eminent.
        [1913 Webster] -- Re*mark"a*ble*ness, n. --
        Re*mark"a*bly, adv.
        [1913 Webster]

WordNet (r) 3.0 (2006):

remarkably
    adv 1: to a remarkable degree or extent; "she was unusually
           tall" [syn: unusually, remarkably, outstandingly,
           unco] [ant: commonly, normally, ordinarily,
           unremarkably, usually]
    2: in a signal manner; "signally inappropriate methods" [syn:
       signally, unmistakably, remarkably]

Moby Thesaurus II by Grady Ward, 1.0:

80 Moby Thesaurus words for "remarkably":
   abundantly, acutely, amazingly, amply, astonishingly, awesomely,
   awfully, beguilingly, bewilderingly, consequentially,
   conspicuously, copiously, eminently, emphatically, enigmatically,
   exceedingly, exceptionally, exquisitely, extraordinarily,
   extremely, exuberantly, fabulously, famously, fantastically,
   fascinatingly, generously, glaringly, grandly, greatly, highly,
   importantly, impressively, incomprehensibly, inconceivably,
   incredibly, ineffably, intensely, magically, magnanimously,
   magnificently, markedly, marvelously, materially, miraculously,
   momentously, nobly, notably, outlandishly, outstandingly,
   particularly, peculiarly, phenomenally, pointedly, preeminently,
   prodigiously, profusely, prominently, pronouncedly, puzzlingly,
   richly, saliently, sensationally, signally, significantly,
   singularly, splendidly, strangely, strikingly, stupendously,
   superlatively, surpassingly, surprisingly, uncommonly,
   unimaginably, unspeakably, unusually, wonderfully, wondrous,
   wondrously, worthily