'Edge' in the Bible

From Aroer on the edge of Arnon Valley and from the town all the way to Gilead, there was no city that was too strong for us the LORD our God delivered them all to us.

“So we took possession of this land at that time. I gave the territory from Aroer, which is by the valley of the Arnon, along with half of the hill country of Gilead and its cities to the Reubenites and to the Gadites.

from Aroer on the edge of the Wadi Arnon as far as Mount Sirion, which is also called Hermon,

Thou shalt surely smite the inhabitants of that city with the edge of the sword, destroying it utterly, and all that is therein, and the cattle thereof, with the edge of the sword.

And when the LORD thy God hath delivered it into thine hands, thou shalt smite every male thereof with the edge of the sword: