Planetary is an adjective that describes something related to or characteristic of planets, which are celestial objects that orbit around stars. The term is derived from the word "planet," which refers to a celestial body that revolves around a star, is roughly spherical in shape, and has cleared its orbit of other debris.
In astronomical contexts, "planetary" refers to anything related to planets or the study of planets. It can describe the physical aspects, properties, or phenomena associated with these celestial bodies. For example, planetary science is a discipline that examines the formation, characteristics, and behavior of planets.
The term can also be used metaphorically to describe something that resembles or relates to a planet in some way. In this sense, it implies a large-scale or comprehensive nature. For example, a "planetary system" refers to a group of planets orbiting a star, and a "planetary orbit" describes the path or trajectory followed by a planet in its revolution around its star.
Furthermore, "planetary" can also refer to a celestial body or object that functions or acts like a planet. For instance, dwarf planets such as Pluto have planetary properties but might not meet all the criteria to be officially classified as a planet.
In summary, the term "planetary" generally pertains to planets, their properties, phenomena, or anything related to them. It encompasses the scientific study of planets, metaphorical representations, and celestial bodies resembling or functioning as planets.
