Buff vs GI

Buff

noun
  • A member of the Buffs (Royal East Kent Regiment). 

name
  • A surname. 

GI

noun
  • A member of the U.S. military. 

  • One who is demanding and strict, in the manner of a stereotypical member of the military. 

verb
  • To clean aggressively. 

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