Smith's Bible Dictionary
Adum'mim. (the going up to). A rising ground or pass over against Gilgal, and "on the south side of the 'torrent', " Joshua 15:7; Joshua 18:17, which is the position still occupied by the road leading up from Jericho and the Jordan valley to Jerusalem, on the south face of the gorge of the Wady Kelt. Luke 10:30-36.
These files are public domain.
Smith, William, Dr. Entry for 'Adummim'. Smith's Bible Dictionary. https://www.studylight.org/dictionaries/eng/sbd/a/adummim.html. 1901.