in botany, a genus of the polygamia monoecia clas. The calyx of the hermaphrodite flower has five leaves; it has no corolla; the stamens are five, and the stylus is divided into two parts; there is but one depressed seed. The calyx of the female flower has two leaves; it has no corolla nor stamens; the stylus is divided into two parts; and there is but one depressed seed. The species are 12, of which eight are natives of Britain; viz. the portulacoides, or sea-purslane; the lacinea, or jagged sea-orache; the hastata, or spear-leaved orache; the erecta, or wild orache; the patula, or narrow-leaved orache; the ferrata, or indented. indented sea-orache; the littoralis, or grass-leaved orache, and the pedunculata, or stalked sea-orache.