The Collaborative International Dictionary of English v.0.48:

madrona \ma*dro"na\, madrona \ma*dro"[~n]a\, madrono
\ma*dro"no\, n. [Sp. madro[~n]o.] (Bot.)
   A small evergreen tree or shrub (Arbutus Menziesii), of
   Pacific North America, having a smooth bark, thick glossy
   leathery leaves, and edible orange-red berries, which are
   often called madro[~n]a apples; the wood is used for
   furniture and the bark for tanning. [Written also
   madro[~n]o.]

   Syn: madrona, manzanita, Arbutus menziesii.
        [1913 Webster + WordNet 1.5]

WordNet (r) 3.0 (2006):

madrona
    n 1: evergreen tree of the Pacific coast of North America having
         glossy leathery leaves and orange-red edible berries; wood
         used for furniture and bark for tanning [syn: madrona,
         madrono, manzanita, Arbutus menziesii]