casteism vs racialism

casteism

noun
  • discrimination based on a person's caste 

racialism

noun
  • The belief that humans can be categorized as belonging to distinct races, each race being characterized by fixed and heritable traits. 

  • Racism, belief in different races and that some are superior; policies or practices promoting the dominance of one or more races over others. 

How often have the words casteism and racialism occurred in a corpus of books? (source: Google Ngram Viewer )