milkwagon vs wagon

milkwagon and wagon both are nouns.

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

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

milkwagon: wagon for delivering milk
wagon: any of various kinds of wheeled vehicles drawn by an animal or a tractor

Other hypernyms of milkwagon include waggon.

milkwagon (noun)	wagon (noun)
wagon for delivering milk	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