cruiser vs warship

cruiser and warship both are nouns.

Word	Noun	Adjective	Verb	Adverb
cruiser	Yes	No	No	No
warship	Yes	No	No	No

As nouns, warship is a hypernym of cruiser; that is, warship is a word with a broader meaning than cruiser:

cruiser: a large fast warship; smaller than a battleship and larger than a destroyer
warship: a government ship that is available for waging war

Other hypernyms of cruiser include combat ship, war vessel.

cruiser (noun)	warship (noun)
a large fast warship; smaller than a battleship and larger than a destroyer	a government ship that is available for waging war
a large motorboat that has a cabin and plumbing and other conveniences necessary for living on board
a car in which policemen cruise the streets; equipped with radiotelephonic communications to headquarters