Piggy bank
This is traditionally a container where money is kept. It was often in the form of a pig, but with time, it has changed to any container. The most common container is a box, which is not easy to break open or have access to until you are certain you really need the money in it. With a piggy bank, instead of using loose change to buy savouries and other petty items, you can put them in the piggy bank and watch the money grow.