altar vs sacrarium

altar

noun
  • A raised area around an altar in a church; the sanctuary. 

  • A table or similar flat-topped structure used for religious rites. 

  • Any (real or notional) place where something is worshipped or sacrificed to. 

sacrarium

noun
  • The area surrounding the altar of a Christian church; the sanctuary or piscina. Sometimes specifically a drain directly to the earth, perhaps including reference to a basin, for washing vessels from consecration. 

  • In Ancient Rome, a place where sacred objects were kept, either in a temple (the adytum) or in a house (holding the penates) 

  • The complex sacrum of any bird. 

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