Shur: An enclosure; a wall, a part, probably, of the Arabian desert, on the
north-eastern border of Egypt, giving its name to a wilderness
extending from Egypt toward Philistia
(Genesis 16:7; 20:1; 25:18; Exodus 15:22)
The name was probably given to it from the wall (or shur) which the
Egyptians built to defend their frontier on the north-east from the
desert tribes. This wall or line of fortifications extended from
Pelusium to Heliopolis.