grade nine vs youngest

grade nine

noun
  • Ninth grade. 

youngest

noun
  • The youngest child in a family, or individual in a group. 

adj
  • Most recently begun or formed. 

  • Receiving dealt cards last, i.e. immediately before the next deal to the eldest. 

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