The "orbital period" refers to the time it takes for an object to complete one full orbit around another object in space. For example, the Earth has an orbital period of about 365.25 days as it revolves around the Sun. This period can vary significantly depending on the distance from the central object and the mass of the orbiting body. Different celestial bodies have different orbital periods. For instance, Mars takes about 687 Earth days to orbit the Sun, while Mercury completes its orbit in just 88 Earth days. These variations are influenced by gravitational forces and the shape of the orbit.