Yes, and you've highlighted the bit that isn't the actual definition.I didn’t google theories of racism. I googled racism and theories of racism is a tag google have applied.
It’s not that deep
Why don’t you see if you can find a link that from a decent source that backs up your view that racially stereotyping isn’t racism.
You're right, it's not that deep. It's a pretty simple definition if you understand what discrimination, antagonism and prejudice mean. You shouldn't need me to explain the difference between the two if that's the case. If you want to argue with the Oxford dictionary then be my guest. See how you get on.