'Brook' in the Bible

“The south side, southward, from Tamar [near the Dead Sea] shall extend as far as the waters of Meribath-kadesh, to the Brook of Egypt and to the Great [Mediterranean] Sea. This is the south side toward the south.

And beside the border of Gad, at the south side, southward, the border shall extend from Tamar to the waters of Meribath-kadesh, to the Brook [of Egypt], to the Great [Mediterranean] Sea.