marabout vs nymphaeum

marabout

noun
  • The tomb or shrine of such a person. 

  • A Muslim holy man or mystic, especially in parts of North Africa. 

nymphaeum

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

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