freedom fighter vs meliorist

freedom fighter and meliorist both are nouns.

Word	Noun	Adjective	Verb	Adverb
freedom fighter	Yes	No	No	No
meliorist	Yes	No	No	No

As nouns, meliorist is a hypernym of freedom fighter; that is, meliorist is a word with a broader meaning than freedom fighter:

freedom fighter: a person who takes part in an armed rebellion against the constituted authority (especially in the hope of improving conditions)
meliorist: a disputant who advocates reform

Other hypernyms of freedom fighter include crusader, reformer, reformist, social reformer, revolutionary, revolutionist, subversive, subverter.

freedom fighter (noun)	meliorist (noun)
a person who takes part in an armed rebellion against the constituted authority (especially in the hope of improving conditions)	a disputant who advocates reform