in botany: A genus of the angiospermia order, belonging to the didynamia clas of plants; and in the natural method ranking under the 49th order, Peronatae. The calyx is pentaphyllous; the limb of the corolla quinqued and equal; with its lobes emarginated, and the upper lip very short and reflexed; the capsule bilocular. There are six species, none of them natives of Britain. They grow from two inches to four feet in height, and are adorned with flowers of a white or purple colour. They are propagated by seeds, but in this country generally require to be kept in a stove.