prisoner vs yardbird

prisoner

noun
  • A person incarcerated in a prison, while on trial or serving a sentence. 

  • Any person held against their will. 

  • A person who is or feels confined or trapped by a situation or a set of circumstances. 

yardbird

noun
  • A person who is imprisoned. 

  • A chicken. 

  • A soldier who is required to perform menial work on the grounds of a military base. 

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