town vs ghost town

town and ghost town both are nouns.

Word	Noun	Adjective	Verb	Adverb
town	Yes	No	No	No
ghost town	Yes	No	No	No

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

Other hyponyms of town include burg, boom town, cow town, cowtown, hometown, Main Street, market town.

town (noun)	ghost town (noun)
the people living in a municipality smaller than a city	a deserted settlement (especially in western United States)
an urban area with a fixed boundary that is smaller than a city
an administrative division of a county