half blood vs half-caste

half blood

noun

  • A person whose father and mother are of different races; a half-breed 

  • A person who shares one parent with another; a half-sibling. 

half-caste

noun

  • A person of mixed racial descent. 

adj

  • Of mixed racial descent. 

How often have the words half blood and half-caste occurred in a corpus of books? (source: Google Ngram Viewer )