bell pepper vs capsicum

bell pepper

noun
  • Capsicum annuum, an edible spicy-sweet fruit, originating in the New World. 

capsicum

noun
  • Any of several tropical American plants, of the genus Capsicum, principally the species Capsicum annuum and Capsicum frutescens, that are cultivated as edible peppers. 

  • The spicy fruit of the above plants, the bell pepper. 

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