fighter vs shielder

fighter and shielder both are nouns.

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

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

Other hypernyms of fighter include defender, guardian, protector.

fighter (noun)	shielder (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