black pepper vs sweet pepper

black pepper

noun
  • The dried, unripe berries (peppercorns) of the Piper nigrum plant which are commonly used as a spice and seasoning. They are either used whole, or in a ground or crushed form. 

  • The plant Piper nigrum. 

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 black pepper and sweet pepper occurred in a corpus of books? (source: Google Ngram Viewer )