From Webster's.  1 and 2 don't apply in this case, #3 is what I was referring to.
Definition of racism 
1
:  a belief that race is the primary determinant of human traits and capacities and that racial differences produce an inherent superiority of a particular race
2
a :  a doctrine or political program based on the assumption of racism and designed to execute its principles
b :  a political or social system founded on racism
3
:  racial prejudice or discrimination