bitterwood

from The Century Dictionary.

• noun The timber of Xylopia glabra, and other species of the same genus. All of them are noted for the extreme bitterness of their wood.
• noun A name applied to the quassia woods of commerce, the West Indian Picræna excelsa and the Surinam Quassia amara. See quassia.

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

• noun A West Indian tree (Picræna excelsa) from the wood of which the bitter drug Jamaica quassia is obtained.

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

• noun quassia

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

• noun medium to large tree of tropical North and South America having odd-pinnate leaves and long panicles of small pale yellow flowers followed by scarlet fruits
• noun West Indian tree yielding the drug Jamaica quassia
• noun handsome South American shrub or small tree having bright scarlet flowers and yielding a valuable fine-grained yellowish wood; yields the bitter drug quassia from its wood and bark