👉 In mathematics, a surrounder is a type of object that can be placed within another object. It is analogous to placing an object into a container or bag. For example, consider a box with two shelves, and one shelf is empty. If you were to place a book in the empty shelf, it would become the "surrounder" of the book. Similarly, if you were to fill one of the shelves with books, it would become the "surrounder" of those

surrounder