Matthew Poole and continuators on 2 Samuel 8:1

AND after this it came to pass, that David smote the Philistines, and subdued them: and David took Metheg-Ammah out of the hand of the Philistines.

i. e. Gath and her Towns, as it is expressed in the parallel place, 1 Chron. 18. 1. which are called Metheg-Ammah, or the Bridle of Ammah, because Gath was situate in the Mountain of Ammah; and because this being the chief City of the Philistines, and having a King, which none of the rest had, was the Bridle which had hitherto kept the Israelites in subjection, but now was taken out of their mouths.

Marginal references: Or, the bridle of Ammah▪