An "ellipsoidal" shape refers to an elongated sphere, resembling an oval or an egg. It is defined mathematically as a surface formed by rotating an ellipse around one of its principal axes. This shape is commonly found in nature, such as in the form of planets like Earth and Jupiter, which are not perfect spheres but rather slightly flattened at the poles. In various fields, such as geometry and astronomy, ellipsoidal shapes are important for understanding the properties of objects. For example, the ellipsoid model is used to represent the shape of the Earth in geodesy, helping to improve navigation and mapping accuracy.