Do you really think you would have to go all the way to a college professor just to get an example of racism?
Also, it's trivial to "refute" an opponents argument if you get to define what all of his terms mean. All you would be accomplishing is an exercise in intellectual dishonesty.
Via the principle of explosion, if you are allowed to contradict your opponent at whim, then you could literally "prove" anything you wanted, meaning that any such argument would be inherently absurd and meaningless.