Thou daughter that dost inhabit Dibon, come down from thy glory, and sit in thirst; for the spoiler of Moab shall come upon thee, and he shall destroy thy strong holds. Thou daughter - (Isaiah 47:1, "O virgin daughter of Babylon").
That dost inhabit - now so securely settled, as if in a lasting habitation.
Sit in thirst - Dibon, being situated on the Arnon, abounded in water (Isaiah 15:9). In sad contrast with this, and with her "glory" in general, she shall be reduced not only to shame, but to the want of the commonest necessaries ("thirst") in the arid wilderness (Jeremiah 48:6).
He shall destroy thy strongholds. There are found by travelers now relics of gigantic masonry, without cement, in the hilly parts of the Moabite, region, such as look like rude fastnesses and "strongholds" of giants. There were before the Israelite occupation of the country many giants in Canaan.