political prisoner vs prisoner

political prisoner and prisoner both are nouns.

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

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

political prisoner: someone who is imprisoned because of their political views
prisoner: a person who is confined; especially a prisoner of war

Other hypernyms of political prisoner include captive.

political prisoner (noun)	prisoner (noun)
someone who is imprisoned because of their political views	a person who is confined; especially a prisoner of war