van vs wagon

van and wagon both are nouns.

Word	Noun	Adjective	Verb	Adverb
van	Yes	No	No	No
wagon	Yes	No	No	No

As nouns, wagon is a hyponym of van; that is, wagon is a word with a more specific, narrower meaning than van:

van (noun)	wagon (noun)
a truck with an enclosed cargo space	any of various kinds of wheeled vehicles drawn by an animal or a tractor
a camper equipped with living quarters	a car that has a long body and rear door with space behind rear seat
(Great Britain) a closed railroad car that carries baggage or freight	van used by police to transport prisoners
the leading units moving at the head of an army	a child's four-wheeled toy cart sometimes used for coasting
any creative group active in the innovation and application of new concepts and techniques in a given field (especially in the arts)