DUPLICATUM JUS, a twofold or double right. Those words, according to Bracton, lib. 4, c. 3, signify the same as dreit dreit, or droit droit, and are applied to a writ of right, patent, and such other writs of right as are of the same nature, and do, as it were, flow from it, as the writ of right. Booth on Real Actions, 87.