Palatial describes something so large, grand, and luxurious that it resembles a palace. A palatial home might have marble floors, soaring ceilings, crystal chandeliers, and dozens of rooms. A palatial hotel lobby could feature sweeping staircases, ornate decorations, and enough space to hold hundreds of people comfortably.

The word comes from “palace,” those enormous royal residences where kings and queens lived. When you call something palatial, you're saying it has that same sense of magnificence and scale. A palatial estate might sprawl across acres of land with gardens, fountains, and wings dedicated to different purposes.

You can use palatial with a hint of exaggeration or humor too. If your friend's new bedroom seems huge compared to your own, you might joke that they've moved into palatial quarters. The word emphasizes size, elegance, and impressiveness all at once. An airplane hangar is huge, but it's not palatial. A mansion with gold-trimmed furniture, priceless artwork, and ballrooms? That's palatial.