3 occurrences in 3 dictionaries
Reference: Dimon
Fausets
E. of the Dead Sea in Moab (Isa 15:9). Probably equating to Dibon, as a play between it and dam, "blood"; Dimon's waters shall be full of dam.
Morish
Di'mon Waters of.
Streams east of the Salt Sea. Isa 15:9.
Smith
Di'mon
(river bed), The waters of, some streams on the east of the Dead Sea, in the land of Moab, against which Isaiah uttered denunciation.
Gesenius conjectures that the two names Dimon and Dibon are the same.