planet wheel vs geared wheel

planet wheel and geared wheel both are nouns.

Word	Noun	Adjective	Verb	Adverb
planet wheel	Yes	No	No	No
geared wheel	Yes	No	No	No

As nouns, geared wheel is a hypernym of planet wheel; that is, geared wheel is a word with a broader meaning than planet wheel:

planet wheel: an outer gear that revolves about a central sun gear of an epicyclic train
geared wheel: a toothed wheel that engages another toothed mechanism in order to change the speed or direction of transmitted motion

Other hypernyms of planet wheel include cogwheel, gear, gear wheel.

planet wheel (noun)	geared wheel (noun)
an outer gear that revolves about a central sun gear of an epicyclic train	a toothed wheel that engages another toothed mechanism in order to change the speed or direction of transmitted motion