What, exactly, is Racism?

The word is thrown around and can mean anything you want it to. So define it in your own words, not Oxford or Merriam Webster.
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In my view, Racism is a belief in the inherent inferiority of a racial group such that the believing group has the "license" to control, mistreat and harm them. Any representative of any racial group can be racist against another group.
What, exactly, is Racism?
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