pugilist vs fighter

pugilist and fighter both are nouns.

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

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

Other hypernyms of pugilist include battler, belligerent, combatant, scrapper.

pugilist (noun)	fighter (noun)
someone who fights with his fists for sport	a high-speed military or naval airplane designed to destroy enemy aircraft in the air
	someone who fights (or is fighting)
	someone who fights for a cause