Truss (from O. Fr. trusser, trosser, torser, trousser, to pack, bind, gird up, Low Lat. tortiare, formed from tortus, twisted, torquere, to twist; cf. "torch" and "trousers," also trousseau, a bride's outfit, literally a small pack or bundle), a pack or bundle, applied specifically to a quantity of hay or straw tied together in a bundle. A truss of straw contains 36 lb, of old hay 56 lb, of new hay 60 lb. A load contains 36 trusses. The term is also used generally of a supporting frame or structure, especially in the construction of a roof or a bridge. It is thus used as the name of a surgical appliance, a belt with an elastic spring keeping in place a pad used as a support in cases of hernia.