city state vs body politic

city state and body politic both are nouns.

Word	Noun	Adjective	Verb	Adverb
city state	Yes	No	No	No
body politic	Yes	No	No	No

As nouns, body politic is a hypernym of city state; that is, body politic is a word with a broader meaning than city state:

city state: a state consisting of a sovereign city
body politic: a politically organized body of people under a single government

Other hypernyms of city state include commonwealth, country, land, nation, res publica, state.

city state (noun)	body politic (noun)
a state consisting of a sovereign city	a politically organized body of people under a single government