bilboes vs detention

bilboes

noun
  • An iron bar fitting around the ankles of prisoners, and having sliding shackles. 

detention

noun
  • Confinement of a prisoner awaiting trial. 

  • The bare physical control without the mental element of intention required for possession. 

  • The act of detaining or the state of being detained. 

  • A punishment given to a student for a minor infraction, typically requiring the student to report to a designated room during recess or outside of school hours to work on homework or perform busywork. 

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