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):

superb
    adj 1: of surpassing excellence; "a brilliant performance"; "a
           superb actor" [syn: brilliant, superb]
    2: surpassingly good; "a superb meal"