Capacious means having a lot of space inside, able to hold or contain a large amount. A capacious backpack can fit all your textbooks, your lunch, your gym clothes, and still have room left over. A capacious closet is one where you can store winter coats, board games, sports equipment, and boxes of old toys without everything getting squashed together.

When you say a container is capacious, you're emphasizing its roomy interior and its ability to accommodate more than you might expect. A capacious car trunk can fit everyone's luggage for a family road trip. A capacious memory can hold years of facts, stories, and experiences.

You'll often see capacious used to describe bags, rooms, or other containers, but it can describe anything with impressive holding power. Writers sometimes describe a capacious mind as one that can understand and remember many complex ideas. The word emphasizes useful internal space, the kind that makes you think, “Wow, I can fit so much in here!”