a genus of plants belonging to the nat. ord. Gentianaceae. It includes about a hundred species, many of them remarkable for the beauty of their flowers, which are usually of different shades of blue, but sometimes red, purple, yellow, or rose-coloured. See Botany, vol. v., p. 200. The officinal gentian is the dried root of *Gentiana lutea*, a native of the Alps, which has a stem about three feet high, broad ovate leaves, and numerous yellow flowers. It has an intensely bitter taste, and is in general use as a tonic in diseases of debility. Its febrifuge virtues have been celebrated from antiquity, and it was a much-valued remedy in intermittents before the introduction of cinchona, for which it is still sometimes substituted. All the species contain the bitter principle in abundance.