aft vs vanguard

aft

adj
  • located at the back of a boat, ship, or airplane 

adv
  • At, near, or towards the stern of a vessel (with the frame of reference within the vessel). 

noun
  • The stern portion of a vessel. 

vanguard

noun
  • The person(s) at the forefront of any group or movement. 

  • The leading units at the front of an army or fleet. 

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