The part of the cell that stores water is called the vacuole.

Here's why:

* Large central vacuole: Plant cells have a large, central vacuole that takes up most of the cell's volume. This vacuole is filled with water and other dissolved substances, which helps to maintain the cell's turgor pressure (the pressure that keeps the cell rigid).

* Smaller vacuoles: Animal cells also have vacuoles, but they are generally smaller and more numerous. These vacuoles can store water, as well as other materials like nutrients and waste products.

So, while other parts of the cell might contain some water, the vacuole is the primary storage location for water in both plant and animal cells.