Meaning of quassia

quas•sia

1. a shrub or small tree, Quassia amara, of tropical America, having pinnate leaves, showy red flowers, and wood with a bitter taste. Cf.
2. any of several other trees having bitter-tasting wood.
3. Also calleda prepared form of the heartwood of any of these trees, used as an insecticide and in medicine as a tonic to dispel intestinal worms.