false indigo

noun

1. any of several North American shrubs belonging to the genus Amorpha, of the legume family, especially A. fruticosa, having compound leaves with pinnate leaflets and long, dense clusters of purplish flowers.
2. any of various plants belonging to the genus Baptisia, of the legume family, native to North America, as B. australis, having trifoliate leaves and long clusters of purplish-blue flowers.