hymn vs nursery rhyme

hymn

noun
  • A song of praise or worship, especially a religious one. 

verb
  • To praise or extol in hymns. 

  • To sing a hymn. 

nursery rhyme

noun
  • A short poem or song for children, mostly anonymous or handed down by folklore 

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