(sebham; Sebama; the King James Version Shebam):

A town in the upland pasture land given to the tribes of Reuben and Gad. It is named along with Heshbon, Elealeh and Nebo (Nu 32:3). It is probably the same place as Sibmah (the King James Version "Shibmah") in Nu 32:38 (so also Josh 13:19). In the time of Isaiah and Jeremiah it was a Moabite town, but there is no record of how or when it was taken from Israel. It appears to have been famous for the luxuriance of its vines and for its summer fruits (Isa 16:8; Jer 48:32). Eusebius (in Onomasticon) calls it a city of Moab in the land of Gilead which fell to the tribe of Reuben. Jerome (Comm. in Isa 5) says it was about 500 paces from Heshbon, and he describes it as one of the strong places of that region. It may be represented by the modern Simia, which stands on the south side of Wady Chesban, about 2 miles from Chesban. The ancient ruins are considerable, with large sarcophagi; and in the neighboring rock wine presses are cut (PEFM, "Eastern Palestine," 221).
W. Ewing