railcar vs wheeled vehicle

railcar and wheeled vehicle both are nouns.

Word	Noun	Adjective	Verb	Adverb
railcar	Yes	No	No	No
wheeled vehicle	Yes	No	No	No

As nouns, wheeled vehicle is a hypernym of railcar; that is, wheeled vehicle is a word with a broader meaning than railcar:

railcar: a wheeled vehicle adapted to the rails of railroad
wheeled vehicle: a vehicle that moves on wheels and usually has a container for transporting things or people

railcar (noun)	wheeled vehicle (noun)
a wheeled vehicle adapted to the rails of railroad	a vehicle that moves on wheels and usually has a container for transporting things or people