A more thorough explanation:

Definition: Pocket money, also known as hat money in maritime law, refers to a small amount of money given to someone for their personal use.

Example: Children often receive pocket money from their parents to spend on small purchases or save for something they want.

Explanation: The example illustrates how pocket money is a small amount of money given to someone, in this case, children, for their personal use. It is usually a small amount of money that can be used for small purchases or saved for something they want. In maritime law, hat money refers to a small gratuity paid to the master of a ship for the care of the cargo.