councillor vs legislator

councillor

noun
  • A member of a council. 

  • In particular, a representative elected to a local authority, such as a city council: a city councillor 

legislator

noun
  • especially a member of a legislative body. 

  • especially not any individual member of a legislative body but the abstracted author of a statute or statutes relevant for the principles of interpretation. 

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