in botany: A genus of the hexandra order, belonging to the dioecia clasps of plants; and in the natural method ranking under the 11th order, Sarmentaceae. The male calyx is sexpartite; there is no corolla; the female calyx is sexpartite; no corolla; three styles; the capsule trilocular and compressed; and there are two membranaceous seeds. There are eight species, of which the only remarkable one is the bulbifera, or yam. This hath triangular winged stalks, which trail upon the ground, and extend a great way: these frequently put out roots from their joints as they lie upon the ground, by which the plants are multiplied. The roots are eaten by the inhabitants of both the Indies; and are particularly serviceable in the West India islands, where they make the greatest part of the negroes food. The plant is supposed to have been brought from the East to the West Indies; for it has never been observed to grow wild in any part of America; but in the island of Ceylon, and on the coast of Malabar, it grows in the woods, and there are in those places a great variety of sorts. It is propagated by cutting the root in pieces, observing to preserve an eye in each, as is practised in planting potatoes. One plant will produce three or four large roots. The skin of these roots is pretty thick, rough, unequal, covered with many stringy fibres or filaments, and of a violet colour approaching to black. The inside is white, and of the consistence of red beer. It resembles the potato in its mealiness, but is of a clover texture. When raw, the yams are viscous and clammy; when roasted or boiled, they afford very nourishing food; and are often preferred to bread by the inhabitants of the West Indies, on account of their lightness and facility of digestion. When first dug out of the ground, the roots are placed in the sun to dry; after which, they are either put into sand, dry garrets, or casks; where, if kept from moisture, they may be preserved whole years, without being spoiled or diminished in their goodness. The root commonly weighs two or three pounds; though some yams have been found upwards of 20 pounds weight.