In'digo, an important vegetable dyestuff, yielding a dye of a deep and lasting blue; the basis also for the best black dye in woolen goods. It has been used in India from an early period, and was imported by the Greeks and Romans. It is obtained from a shrubby plant two or three feet high, with rounded leaves and pale-red flowers, belonging to the family of the bean. At the time of harvest the plant must be three months old and in blossom. The plants are cut down, but soon shoot up again, and yield a second and often a third cutting in one year. Bengal is the chief seat of the indigo trade, and large quantities are imported into our own country and Great Britain. Artificial indigo is now made on a large scale, in Germany, from coal-tar products.