Back vs Tongue

Back

name
  • A settlement on the Isle of Lewis, Western Isles council area, Scotland (OS grid ref NB4840). 

  • A surname. 

Tongue

name
  • A village by the Kyle of Tongue in Sutherland, Highland council area, Scotland (OS grid ref NC5956). 

  • A surname. 

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