Built with vaults — that is, with curved stone or brick ceilings shaped like the inside of an arch, often several arches joined together. You use it about ceilings and roofs: a vaulted ceiling, a vaulted roof, a vaulted hall. Think of an old church, a castle, a cathedral, a wine cellar under a big house — the ceiling goes up and curves over your head instead of being flat. Two feelings come with the word: old and grand. Because vaulting was a way to build big stone roofs before modern steel, the word carries the smell of history, and writers reach for it when they want a place to feel serious and impressive. But modern builders and estate agents also use it loosely, for any ceiling that rises high and slopes up to a point in the middle, even when there is no real arch at all — a wooden A-shaped roof over a living room gets called "vaulted" all the time. That looser use is now normal in house adverts, so don't correct anyone about it. This is nearly always used before the noun (a vaulted ceiling); you would rarely say "the ceiling is vaulted" in speech, though it is fine in writing. Separately, the same spelling is the past form of the verb vault (to jump over something with your hands or a pole) — same origin, quite different meaning, and only context tells you which one you are reading.