flagon vs waterpot

flagon

noun
  • A large vessel resembling a jug, usually with a handle, lid, and spout, for serving drinks such as cider or wine at a table; specifically (Christianity), such a vessel used to hold the wine for the ritual of Holy Communion. 

  • A flagon and its contents; as much as fills such a vessel. 

waterpot

noun
  • A pot or jug for holding water. 

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