(roaring), the river or torrent which formed the boundary between Moab and the Amorites, on the north of Moab, (Numbers 21:13,14,24,26; Judges 11:22) and afterwards between Moab and Israel (Reuben). (2:24,36; 3:8,12,16; 4:48; Joshua 12:1,2; 13:9,16; Judges 11:13,26) There can be no doubt that the Wady el-Mojeb of the present day is the Arnon. Its principal source is near Katrane, on the Haj route.