Boo vs Dull

Boo

name
  • A community in Nacka, Stockholm, central Sweden. 

  • The Boko language. 

Dull

name
  • A village in Perth and Kinross council area, Scotland. 

  • A surname. of Scottish and German origin. 

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