capsicum vs sweet pepper

capsicum

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

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

sweet pepper

noun
  • The fruit of a non-spicy cultivar of pepper, Capsicum annuum, marketed in green-, red-, yellow- and orange-skinned varieties. 

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