A type of argument or debate. An eristic argument is one that is carried out in order to win (and make the other person lose).
Opposed to a dialectic argument, which is more friendly, and is generally carried out in order to find the truth, even if it turns out to be the opposite of the view you are arguing for.
Eristic arguments are fun, but they tend to bar you from coming to any conclusion other than the two held by the two people or groups debating. Dialectic arguments can take you anywhere, and often do.
See also, forensics.