jade vs pack horse

jade

noun
  • A horse too old to be put to work. 

  • A bad-tempered or disreputable woman. 

  • A succulent plant, Crassula ovata. 

  • A semiprecious stone, either nephrite or jadeite, generally green or white in color, often used for carving figurines. 

  • A bright shade of slightly bluish or greyish green, typical of polished jade stones. 

adj
  • Of a grayish shade of green, typical of jade stones. 

verb
  • To fatigue, tire, or weary (someone or something). 

pack horse

noun
  • A horse used for carrying luggage. 

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