dragoon vs troop horse

dragoon

noun
  • A horse soldier; a cavalryman, who uses a horse for mobility, but fights dismounted. 

  • A variety of pigeon. 

  • A carrier of a dragon musket. 

verb
  • To force (someone) into doing something; to coerce. 

  • To surrender (a person) to the fury of soldiers. 

troop horse

noun
  • A cavalry horse. 

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