The Collaborative International Dictionary of English v.0.48:

Superb \Su*perb"\, a. [F. superbe, L. superbus, fr. super over.
   See Super-.]
   1. Grand; magnificent; august; stately; as, a superb edifice;
      a superb colonnade.
      [1913 Webster]

   2. Rich; elegant; as, superb furniture or decorations.
      [1913 Webster]

   3. Showy; excellent; grand; as, a superb exhibition.
      [1913 Webster]

   Superb paradise bird (Zool.), a bird of paradise
      (Paradisaea superba syn. Lophorina superba) having the
      scapulars erectile, and forming a large ornamental tuft on
      each shoulder, and a large gorget of brilliant feathers on
      the breast . The color is deep violet, or nearly black,
      with brilliant green reflections. The gorget is bright
      metallic green.

   Superb warber. (Zool.) See Blue wren, under Wren.
      [1913 Webster] -- Su*perb"ly, adv. -- Su*perb"ness, n.
      [1913 Webster]

WordNet (r) 3.0 (2006):

superbly
    adv 1: (used as an intensifier) extremely well; "her voice is
           superbly disciplined"; "the colors changed wondrously
           slowly" [syn: wonderfully, wondrous, wondrously,
           superbly, toppingly, marvellously, terrifically,
           marvelously]

Moby Thesaurus II by Grady Ward, 1.0:

57 Moby Thesaurus words for "superbly":
   ably, adeptly, adroitly, agilely, aptly, artfully, artistically,
   brilliantly, capably, cleverly, competently, cunningly, deftly,
   dexterously, dextrously, divinely, efficiently, elaborately,
   elegantly, excellently, expertly, exquisitely, extravagantly,
   featly, gloriously, grandiosely, grandly, handily, immensely,
   imposingly, impressively, ingeniously, luxuriously, magnificently,
   majestically, marvelously, masterfully, neatly, nimbly, nobly,
   proficiently, proudly, resourcefully, skillfully, splendaciously,
   splendidly, splendiferously, spryly, sumptuously, terrifically,
   tremendously, well, with consummate skill, with finesse,
   with genius, with skill, wonderfully