major planet vs uranology

major planet and uranology both are nouns.

Word	Noun	Adjective	Verb	Adverb
major planet	Yes	No	No	No
uranology	Yes	No	No	No

major planet (noun)	uranology (noun)
(astronomy) any of the nine large celestial bodies in the solar system that revolve around the sun and shine by reflected light; Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto in order of their proximity to the sun; viewed from the constellation Hercules, all the planets rotate around the sun in a counterclockwise direction	the branch of physics that studies celestial bodies and the universe as a whole