ARROE, a small island of Denmark, in the Baltic sea, a little south of the island of Funen. It is eight miles in length, and about two in breadth; and produces corn, anifeed, black cattle, and horses. It has three parishes, the most considerable of which is Koping. It stands at the south side of the island, in the bottom of a bay, and has a port with some trade. E. Long. 9. 40. N. Lat. 55. 20.