litany vs prayer

litany

noun
  • A ritual liturgical prayer in which a series of prayers recited by a leader are alternated with responses from the congregation. 

  • A prolonged or tedious list. 

prayer

noun
  • A meeting held for the express purpose of praying. 

  • An act of praying. 

  • A practice of communicating with one's God, or with some spiritual entity. 

  • The specific words or methods used for praying. 

  • The remotest hope or chance. 

  • A request; a petition. 

  • One who prays. 

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