(0. Eng. hlaeder; of Teutonic origin, cf. Dutch leer, Ger. Leiter; the ultimate origin is in the root seen in "lean," Gr. icXI aE), a set of steps or "rungs" between two supports to enable one to get up and down; usually made of wood and sometimes of metal or rope. Ladders are generally movable, and differ from a staircase also in having only treads and no "risers." The term "Jacob's ladder," taken from the dream of Jacob in the Bible, is applied to a rope ladder with wooden steps used at sea to go aloft, and to a common garden plant of the genus Polemonium on account of the ladder-like formation of the leaves. The flower known in England as Solomon's seal is in some countries called the "ladder of heaven."