Munro vs Sierra

Munro

name
  • A Scottish surname from Scottish Gaelic, variant of Monroe. 

noun
  • Any Scottish mountain having a height of more than 3,000 feet; named after Sir Hugh Thomas Munro, Scottish mountaineer 

Sierra

name
  • A female given name of modern American usage, from the Spanish noun, confused with Ciara and Sarah. 

  • Sierra Nevada, a mountain range in the United States. 

  • A surname from Spanish. 

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