RV vs motor home

RV and motor home both are nouns.

Word	Noun	Adjective	Verb	Adverb
RV	Yes	No	No	No
motor home	Yes	No	No	No

As nouns, motor home is a hyponym of RV; that is, motor home is a word with a more specific, narrower meaning than RV:

RV: a motorized wheeled vehicle used for camping or other recreational activities
motor home: a recreational vehicle equipped for camping out while traveling

Other hyponyms of RV include camper, camping bus, beach buggy, dune buggy.

RV (noun)	motor home (noun)
a motorized wheeled vehicle used for camping or other recreational activities	a recreational vehicle equipped for camping out while traveling