belvedere vs gazebo

belvedere

noun
  • A turret or other raised structure offering a pleasant view of the surrounding area. 

  • Bassia scoparia (summer cypress) 

gazebo

noun
  • A belvedere, either a type of summer-house or a roofed, detached porch-like structure, usually in a yard, park or lawn. 

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