The Collaborative International Dictionary of English v.0.48:

Ebony \Eb"on*y\, n.; pl. Ebonies. [F. ['e]b[`e]ne, L. ebenus,
   fr. Gr. ?; prob. of Semitic origin; cf. Heb. hobn[imac]m, pl.
   Cf. Ebon.]
   A hard, heavy, and durable wood, which admits of a fine
   polish or gloss. The usual color is black, but it also occurs
   red or green.
   [1913 Webster]

   Note: The finest black ebony is the heartwood of Diospyros
         reticulata, of the Mauritius. Other species of the
         same genus (D. Ebenum, Melanoxylon, etc.), furnish
         the ebony of the East Indies and Ceylon. The West
         Indian green ebony is from a leguminous tree (Brya
         Ebenus), and from the Exc[ae]caria glandulosa.
         [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Ebony \Eb"on*y\, a.
   Made of ebony, or resembling ebony; black; as, an ebony
   countenance.
   [1913 Webster]

         This ebony bird beguiling my sad fancy into smiling.
                                                  --Poe.
   [1913 Webster]

WordNet (r) 3.0 (2006):

ebony
    adj 1: of a very dark black [syn: ebon, ebony]
    n 1: a very dark black [syn: coal black, ebony, jet black,
         pitch black, sable, soot black]
    2: hard dark-colored heartwood of the ebony tree; used in
       cabinetwork and for piano keys
    3: tropical tree of southern Asia having hard dark-colored
       heartwood used in cabinetwork [syn: ebony, ebony tree,
       Diospyros ebenum]