Synonyms for Fighter (same or very similar meaning)
WordNet sense 1 (someone who fights (or is fighting)):
battler, belligerent, combatant, scrapper
WordNet sense 2 (someone who fights for a cause):
champion, hero, paladin
WordNet sense 3 (a high-speed military or naval airplane designed to destroy enemy aircraft in the air):
attack aircraft, fighter aircraft
From the ODE community, based on WordNet
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