aircraft carrier vs combat ship

aircraft carrier and combat ship both are nouns.

Word	Noun	Adjective	Verb	Adverb
aircraft carrier	Yes	No	No	No
combat ship	Yes	No	No	No

As nouns, combat ship is a hypernym of aircraft carrier; that is, combat ship is a word with a broader meaning than aircraft carrier:

aircraft carrier: a large warship that carries planes and has a long flat deck for takeoffs and landings
combat ship: a government ship that is available for waging war

Other hypernyms of aircraft carrier include war vessel, warship.

aircraft carrier (noun)	combat ship (noun)
a large warship that carries planes and has a long flat deck for takeoffs and landings	a government ship that is available for waging war