Definition of Racism

This question pertains to the first debate that took place this Friday, on whether racism was the cause of slavery in America. Both groups included a definition of racism in their opening statements and it is evident that the definition of racism will have a profound effect on whether you view racism as the cause for slavery in America. It is also evident that the definition of racism has been debated and continues to be debated as the con group pointed out. Therefor I was wondering what everyone thought were key points that should be included in the definition of racism.