wain vs wagon

wain and wagon both are nouns.

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

As nouns, wagon is a hypernym of wain; that is, wagon is a word with a broader meaning than wain:

wain: large open farm wagon
wagon: any of various kinds of wheeled vehicles drawn by an animal or a tractor

Other hypernyms of wain include waggon.

wain (noun)	wagon (noun)
large open farm wagon	any of various kinds of wheeled vehicles drawn by an animal or a tractor
	a car that has a long body and rear door with space behind rear seat
	van used by police to transport prisoners
	a child's four-wheeled toy cart sometimes used for coasting