It might not be the definition in a dictionary, but words and their meanings change. For example, literal now means both literal and figurative. When people speak of racism in America they don't mean a dude was mean to them because of the color of their skin.
You can be racist against every race. Anyone who says different is just trying to get away with being racist to white people. They found a way to move the goalposts.
There are systemic and non-systemic ways of defining "racism," each w/ its own history of use. I disagree with people who claim one of these is the correct definition and the other incorrect. There are pros and cons to different definitions, depending on context.