biosphere vs major planet

biosphere and major planet both are nouns.

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

biosphere (noun)	major planet (noun)
the regions of the surface and atmosphere of the Earth (or other planet) where living organisms exist	(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