ampulla vs concavity

ampulla

noun
  • The dilated end of a duct. 

  • An Ancient Roman two-handled vessel. 

  • A vessel for containing consecrated wine or oil. 

  • The spongiole of a root. 

concavity

noun
  • A concave structure or surface 

  • The state of being concave 

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