Concise Bible Dictionary:
District to which captive Israelites were carried (2 Kings 17:6; 2 Kings 18:11; 1 Chron. 5:26). In an Assyrian geographical list the name of Halahhu has been found, which corresponds with Halah, but its position is not well defined. The texts associate it with HABOR.
Strong’s Dictionary of Hebrew Words:
Meaning:
probably of foreign origin; Chalach, a region of Assyria
Potts’ Bible Proper Names:
Moist tablet; moist surface:―a region of Assyria, 2 Kings 17:6. {Tabula humida}