boroughmaster vs constable

boroughmaster

noun
  • The mayor, governor, or bailiff of a borough. 

constable

noun
  • An elected or appointed public officer, usually at municipal level, responsible for maintaining order or serving writs and court orders. 

  • One holding the lowest rank in most Commonwealth police forces. (See also chief constable.) 

  • The warden of a castle. 

  • An officer of a noble court in the Middle Ages, usually a senior army commander. (See also marshal). 

  • A police officer or an officer with equivalent powers. 

  • An elected head of a parish (also known as a connétable) 

  • A large butterfly, Dichorragia nesimachus, family Nymphalidae, of Asia. 

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