changeling vs procurator

changeling

noun
  • A person or object (especially when regarded as inferior) secretly exchanged for something else. 

  • In pre-modern European folklore: an infant of a magical creature that was secretly exchanged for a human infant. In British, Irish and Scandinavian mythology the exchanged infants were thought to be those of fairies, sprites or trolls; in other places, they were ascribed to demons, devils, or witches. 

  • An infant secretly exchanged with another infant deliberately or by mistake; a swapling. 

  • An organism which can change shape to mimic others; a shape-shifter. 

procurator

noun
  • An agent or attorney. 

  • A tax collector. 

  • The governor of a small imperial province. 

  • A legal officer who both investigates and prosecutes crimes, found in some inquisitorial legal systems, particularly communist or formerly communist states – see public procurator 

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