debater

Synonyms:

arguer

Types:

devil's advocate

someone who takes the worse side just for the sake of argument

confuter, disprover, rebutter, refuter

a debater who refutes or disproves by offering contrary evidence or argument

wrangler

someone who argues noisily or angrily

Type of:

controversialist, disputant, eristic

a person who disputes; who is good at or enjoys controversy