altar vs musalla

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. 

musalla

noun
  • A place for praying (e.g. outside a mosque); a praying room. 

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