The Collaborative International Dictionary of English v.0.48:

Mulberry \Mul"ber*ry\, n.; pl. Mulberries. [OE. moolbery,
   murberie, AS. murberie, where the first part is fr. L. morum
   mulberry; cf. Gr. ?, ?. Cf. Murrey, Sycamore.]
   1. (Bot.) The berry or fruit of any tree of the genus
      Morus; also, the tree itself. See Morus.
      [1913 Webster]

   2. A dark pure color, like the hue of a black mulberry.
      [1913 Webster]

   Mulberry mass. (Biol.) See Morula.

   Paper mulberry, a tree (Broussonetia papyrifera), related
      to the true mulberry, used in Polynesia for making tapa
      cloth by macerating and pounding the inner bark, and in
      China and Japan for the manufacture of paper. It is seen
      as a shade tree in America.
      [1913 Webster]

WordNet (r) 3.0 (2006):

mulberry
    n 1: any of several trees of the genus Morus having edible fruit
         that resembles the blackberry [syn: mulberry, mulberry
         tree]
    2: sweet usually dark purple blackberry-like fruit of any of
       several mulberry trees of the genus Morus