nymphaeum vs stupa

nymphaeum

noun
  • An ancient Greek or Roman shrine consecrated to water nymphs, often with a fountain. 

stupa

noun
  • A dome-shaped Buddhist monument, used to house relics of the Lord Buddha. 

  • A stupe (medicated cloth or sponge). 

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