chorister vs songster

chorister

noun
  • A singer in a choir. 

  • A director or leader of a choral group. 

songster

noun
  • A man who sings songs, especially as a profession; a male singer. 

  • One who writes songs. 

  • A male songbird. 

  • A book of songs; songbook. 

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