Alternative form of Planet 9

(planetology) a planet that flies through interstellar space and has no star to encircle

(science fiction) homeworld

(astronomy) Synonym of carbon planet

(astrology, astronomy) The seven non-fixed astronomical objects in the sky visible to the naked eye that where known in Ancient history

(astrology) A planet thought to bring bad luck to those born within its radius

Used other than figuratively or idiomatically: see tertiary, planet. (the third planet; usually counting outwards from the central sun)

(astronomy) a body comparable to a planet, but not a planet, such as a dwarf planet or a planetary-mass moon

(astronomy) A hypothetical type of planet resulting from the atmosphere and outer layers of a gas giant being stripped away, leaving the rocky, metallic core.

(broadcasting) The deliberate inclusion in broadcast media of messages warning about climate change or promoting environmental sustainability.