fighter vs guardian

fighter and guardian both are nouns.

Word	Noun	Adjective	Verb	Adverb
fighter	Yes	No	No	No
guardian	Yes	No	No	No

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

Other hypernyms of fighter include defender, protector, shielder.

fighter (noun)	guardian (noun)
a high-speed military or naval airplane designed to destroy enemy aircraft in the air	a person who cares for persons or property
someone who fights (or is fighting)
someone who fights for a cause