green bean vs snap bean

green bean

noun
  • The immature pods of numerous varieties of the common bean, Phaseolus vulgaris. 

  • The immature pods of any kind of bean plant, eaten as a vegetable. 

snap bean

noun
  • The unripe or green edible fruit pod of a bean plant such as the legume Phaseolus vulgaris. 

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