Oblate spheroid is a term used to describe a shape that resembles a flattened sphere, where the equatorial diameter is larger than the polar diameter. There are several synonyms for oblate spheroid, including ellipsoid, spheroid, flattened sphere, squashed sphere, and ovoid. These terms may be used interchangeably, depending on the context and the field of study. For example, the term ellipsoid is often used in mathematics and geometry, while spheroid is commonly used in earth sciences to describe the shape of the planet. Nonetheless, all these synonyms describe a shape that is not perfectly spherical, but rather distorted in a specific way.