Capacious describes a bag, a pocket, a coat, a room, even a cupboard, that has a lot of space inside. You can put many things in it and it still does not feel full. A capacious handbag can take a bottle of water, a book, and lunch without a fight. In everyday talk people almost never say this word. They say roomy, or big inside, or spacious. You meet capacious in books, in careful writing, and in ads that want to sound a little grand. Writers also stretch it: a capacious mind or a capacious memory can hold many ideas or many facts. That stretch is still about holding, not about being clever. Though actually, the old Latin parent of this word meant both “able to hold a lot” and “able to do something,” and English split those: capacious kept the holding, capable kept the doing. So this is not a louder way to say capable, and it is not a fancy twin of big. Big is how it looks from the outside; capacious is how much room there is inside.

寬敞的、很能裝的（偏書面；口語多說 roomy）