1) Adversary 2) Antagonist 3) Blade 4) Burr or Hamilton 5) Duelist 6) Dueller 7) Duellist 8) Fencing combatant 9) Hamilton or Burr, notably 10) Hamilton or his foe, famously 11) Hamilton, notably 12) Inigo or DP Roberts 13) It takes a second to be one 14) One settling a score 15) One who takes 20 paces 1) Duelist 2) Dueller 3) Duellist 4) Epeeist 
• (n.) One who engages in a duel.
Du'el·er noun One who engages in a duel. [ R.] [ Written also dueller .] South. 
[n] - a person who fights duels
dueller noun a person who fights duels