1) Accentuater of the positive 2) Arguer 3) Be rated as the type to argue 4) Candidate, at times 5) Certain college team member 6) Con, half the time 7) Controversialist 8) Disputant 9) Douglas 10) Douglas or Lincoln 11) Eristic 12) Forensic expert 13) High school team member 14) Lincoln or douglas 1) Arguer 2) Confuter 3) Disprover 4) Disputant 5) Rebutter 6) Refuter 7) Wrangler 
• (n.) One who debates; one given to argument; a disputant; a controvertist.
De·bat'er noun One who debates; one given to argument; a disputant; a controvertist. « Debate where leisure serves with dull debaters .» Shak. 
[n] - someone who engages in debate
arguer noun someone who engages in debate