The Collaborative International Dictionary of English v.0.48:

Belvedere \Bel`ve*dere"\, n. [It., fr. bello, bel, beautiful +
   vedere to see.] (Arch.)
   A small building, or a part of a building, more or less open,
   constructed in a place commanding a fine prospect.
   [1913 Webster]

WordNet (r) 3.0 (2006):

belvedere
    n 1: densely branched Eurasian plant; foliage turns purple-red
         in autumn [syn: summer cypress, burning bush, fire
         bush, fire-bush, belvedere, Bassia scoparia, Kochia
         scoparia]
    2: a gazebo sited to command a fine view