ROSENAU, a city of the Austrian kingdom of Hungary, in the province of the Hither Theiss, and circle of Gomor. It is situated on the river Sajo, and is the seat of a bishop, and of an episcopal seminary. It contains several churches, 680 houses, and 5400 inhabitants, trading in linen, paper, wood-ware, and ironmongery, and also producing good wine. Long. 20. 27. 13. E. Lat. 48. 39. 2. N.