bivalve vs fanny

bivalve

noun
  • A pericarp in which the seed case opens or splits into two parts or valves. 

  • Any mollusc belonging to the taxonomic class Bivalvia, characterized by a shell consisting of two hinged sections, such as a scallop, clam, mussel or oyster. 

fanny

noun
  • Mess kettle or cooking pot. 

  • The female genitalia. 

  • The buttocks; arguably the most nearly polite of several euphemisms. 

  • Women viewed as sexual objects. 

  • Sexual intercourse with a woman. 

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