1. a bitter compound used as an insecticide and tonic and vermifuge; extracted from the wood and bark of trees of the genera Quassia and Picrasma • Hypernyms: organic compound • Hyponyms: Jamaica quassia 2. 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 • Syn: bitterwood, Quassia amara • Hypernyms: bitterwood tree • Member Holonyms: genus Quassia