hostage vs prisoner

hostage and prisoner both are nouns.

Word	Noun	Adjective	Verb	Adverb
hostage	Yes	No	No	No
prisoner	Yes	No	No	No

As nouns, prisoner is a hypernym of hostage; that is, prisoner is a word with a broader meaning than hostage:

hostage: a prisoner who is held by one party to insure that another party will meet specified terms
prisoner: a person who is confined; especially a prisoner of war

Other hypernyms of hostage include captive.

hostage (noun)	prisoner (noun)
a prisoner who is held by one party to insure that another party will meet specified terms	a person who is confined; especially a prisoner of war