A "pentagonal" shape refers to a geometric figure that has five sides and five angles. The term comes from the Greek word "penta," meaning five. A common example of a pentagonal shape is a pentagon, which can be regular (with equal sides and angles) or irregular (with varying lengths and angles). In addition to its geometric meaning, "pentagonal" can also describe structures or patterns that exhibit five-fold symmetry. This concept is often seen in nature, such as in the arrangement of some flowers or starfish, where the pentagonal symmetry plays a role in their overall design and function.