AR (anc. geog.), the metropolis of Moab, in Arabia Petrea (Moses); and the royal residence situate on the east side of the river Arnon. It was called also Rabba (Joshua); and to distinguish it from Rabba of the Ammonites, Rabbat Moab, and on coins Rabbath Moma (Reland). Eusebius says it was called Acropolis in his time, from Ar and Polis. The inhabitants are called Acropolites. St Jerome says that this city was entirely destroyed by an earthquake when he was a young man.