'Royal' in the Bible

That they feared greatly, because Gibeon was a great city, as one of the royal cities, and because it was greater than Ai, and all the men thereof were mighty.

Joshua captured all these royal cities and all their kings and annihilated them with the sword, as Moses the Lord's servant had commanded.

But half of Gilead, and Og’s royal cities in Bashan—Ashtaroth and Edrei—are for the descendants of Machir son of Manasseh, that is, half the descendants of Machir by their clans.