The Collaborative International Dictionary of English v.0.48:

manzanita \man`za*ni"ta\ (m[a^]n`z[.a]*n[=e]"t[.a]), n. [Sp.,
   dim. of manzana an apple.] (Bot.)
   A name given to several species of Arctostaphylos, but
   mostly to Arctostaphylos glauca and Arctostaphylos
   pungens, shrubs of California, Oregon, etc., with reddish
   smooth bark, ovate or oval coriaceous evergreen leaves, and
   bearing clusters of red berries, which are said to be a
   favorite food of the grizzly bear.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Arctostaphylos \Arctostaphylos\ n.
   1. 1 a genus of plants including the bearberry; manzanita.

   Syn: genus Arctostaphylos.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

Arctostaphylos
    n 1: bearberry; manzanita [syn: Arctostaphylos, genus
         Arctostaphylos]