Here it is...
Gilgal = "rolled back".
The reproach of Egypt was that the Egyptians told the children of Israel that God would kill them all in the wilderness.
Which of course did not happen. In fact God preserved them with loving care in the wilderness.
Jos 5:9
And the LORD said unto Joshua, This day have I rolled away the reproach of Egypt from off you. Wherefore the name of the place is called Gilgal unto this day.