betty vs sponge cake

betty

noun
  • A baked dessert made with alternating layers of sweetened fruit and buttered bread crumbs. 

  • An attractive woman; a babe. 

  • A short bar used by thieves to wrench doors open; a jimmy. 

sponge cake

noun
  • A light, soft, baked dessert (commonly layered with cream and jam) that is typically made with flour, sugar, baking powder and eggs, and has a firm, yet well aerated structure, similar to that of a sea sponge. 

How often have the words betty and sponge cake occurred in a corpus of books? (source: Google Ngram Viewer )