The term "expiration date" refers to the last day that a product is guaranteed to be at its best quality and effectiveness. It indicates the time by which a perishable item should be consumed or used before it goes bad, loses its potency, or becomes unsafe for consumption. The expiration date is usually printed on packaged foods, medications, cosmetics, and other products that have a limited shelf life. It helps to ensure the safety of consumers by preventing them from using outdated or spoiled items.