What does "omnibus" mean?

Omnibus: (Glass Making) A sheet-iron cover for articles in a leer or annealing arch, to protect them from drafts. Omnibus bill, a legislative bill which provides for a number of miscellaneous enactments or appropriations. [Parliamentary Cant, U.S.] -- Omnibus box, a large box in a theater, on a level with the stage and having communication with it. [Eng.] Thackeray.