a genus of plants of the family Leguminosae. They are trees, climbing shrubs, or woody lianas. The leaves are alternate and odd-pinnate, and the flowers are violet, purple, or white, growing in racemes or panicles. There are as many as 150 species in the tropics of America, Africa, and Australia. Some species yield valuable wood. A blue dye is obtained from the leaves and young sprouts of L. cyanescens (from tropical West Africa). The roots of L. utilis and L. urucu, which grow in South America, are used to obtain a poison that is used as an insecticide.