ambo vs dais

ambo

noun
  • A stationary podium used for readings and homilies. 

  • An ambulance driver. 

  • A raised platform in an early Christian church, as well as in the Eastern Orthodox, Oriental Orthodox, and Eastern Catholic churches. 

  • An ambulance. 

dais

noun
  • A raised platform in a room for a high table, a seat of honour, a throne, or other dignified occupancy, such as ancestral statues; a similar platform supporting a lectern, pulpit, etc., which may be used to speak from. 

  • The canopy over an altar, etc. 

  • A bench, a settle, a pew. 

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