Something collapsible is made so you can fold it, slide it, or push it down and it takes up much less space. A collapsible chair opens when you sit and folds flat when you carry it; tables, strollers, cups, walking sticks, and even some boats can be collapsible too. Shops put the word on boxes and product pages because buyers care about storage. Though actually, it does not always mean “folds like paper.” Sometimes the parts just tuck into each other. And it is not the same as collapsed: collapsed means it has already fallen down, often by accident. Collapsible means you can fold it on purpose, and then open it again.