borstal vs prison

borstal

noun
  • Any institution which provides education to young offenders. 

  • Any of the prisons set up in Britain for delinquent boys from 1895 to 1983. 

  • A way up a hill in the South Downs. 

prison

noun
  • Confinement in prison. 

  • A place or institution where people are held against their will, especially for long-term confinement of those awaiting trial or convicted of serious crimes or otherwise considered undesirable by the government. 

  • Any restrictive environment, such as a harsh academy or home. 

verb
  • To imprison. 

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