afro vs dreadlocks

afro

noun
  • hairstyle characterized by tightly curled locks and a rounded shape. 

  • A person of African ancestry 

dreadlocks

noun
  • A hairstyle worn by Rastafarians and others in which the hair is left to grow into long matted strings. 

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