Circle vs Metropolis

Circle

name
  • A town, the county seat of McCone County, Montana, United States. Named after a cattle brand in the form of a circle. 

  • A census-designated place in Yukon-Koyukuk Census Area, Alaska, United States. Erroneously thought to be on the Arctic Circle, which is 50 miles further north. 

  • the Circle line of the London Underground, originally the Inner Circle. 

  • A surname from German. 

Metropolis

name
  • A ghost town in Elko County, Nevada, United States. 

  • A city, the county seat of Massac County, Illinois, United States. 

  • a classical city site in Anatolia (Turkey). 

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