A safety deposit box is a secure vault used for storing valuable items, documents, and cash. However, there are several synonyms that you can use for a safety deposit box, including safekeeping, lockbox, strongbox, security box, vault, and deposit locker. These terms are commonly used in financial institutions, such as banks, where they offer safe and secure storage for customers. Depending on the purpose of the storage, the synonyms used for a safety deposit box are interchangeable. Regardless of the term used, the main aim of these secure storage facilities is to provide a safe haven for valuable possessions, protecting them from theft, damage, or loss.