common bean vs pea bean

common bean

noun
  • An herbaceous annual plant (Phaseolus vulgaris), grown for its edible bean. 

  • A bean of such a plant, varying in size, shape and especially color. 

pea bean

noun
  • A very small and highly esteemed variety of the edible white bean. 

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