gallows-tree vs gibbet

gallows-tree

gibbet

noun
  • An upright post with a crosspiece used for execution and subsequent public display. 

  • The projecting arm of a crane, from which the load is suspended; the jib. 

  • A human-shaped structure made of iron bands designed to publicly display the corpse of an executed criminal. 

verb
  • To expose (someone) to ridicule or scorn. 

  • To execute (someone), or display (a body), on a gibbet. 

How often have the words gallows-tree and gibbet occurred in a corpus of books? (source: Google Ngram Viewer )