DRABA, in botany, a genus of the tetradymania siliculosa class. The pod is entire and somewhat oval, with plain valves, and a parallel disseptimentum; it has no stylus. There are six species, three of them natives of Britain, viz. the verna, or common whistow-grass; the muralis, or speedwell-leaved whistow-grass; and the incana, or wreathen poded whistow-grass.