'Border' in the Bible

Thus saith the LORD; For three transgressions of the children of Ammon, and for four, I will not turn away the punishment thereof; because they have ripped up the women with child of Gilead, that they might enlarge their border:

Pass ye unto Calneh, and see; and from thence go ye to Hamath the great: then go down to Gath of the Philistines: be they better than these kingdoms? or their border greater than your border?