in botany: A genus of the monogynia order, belonging to the pentandria clas of plants; and in the natural method ranking under the 30th order, Contortae. There are two erect follicles; the seeds plump; the tube of the corolla terminated by a lacerated crown. There are five species, all of them natives of the warmer climates: the most remarkable of which are, 1. The oleander, South-Sea rose: this is a beautiful shrub, cultivated in gardens on account of its flowers, which are of a fine purple, and in clutters, but of an indifferent smell: the whole plant is poisonous, and especially the bark of the roots. 2. The antidysentericum, a native of Ceylon: the bark of which is an article of materia medica, under the name of Coneffii. 3. The tinctorium, a new species with beautiful blue flowers lately discovered by Dr Rozburgh at Madras. A decoction of the leaves, with an addition of lime-water, makes an indigo of fine quality.