ebonize

from The American Heritage® Dictionary of the English Language, 5th Edition.

• transitive verb To stain black like ebony.

from The Century Dictionary.

• To stain black, as wood, with a view to the imitation of natural ebony: as, a bookcase of ebonized wood.
• To make black or tawny; tinge with the color of ebony: as, to ebonize the fairest complexion. Also spelled ebonise.

from the GNU version of the Collaborative International Dictionary of English.

• transitive verb To make black, or stain black, in imitation of ebony.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• verb transitive To give wood the color or texture of ebony.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• verb stain black to make it look like ebony