impalement vs piercing

impalement

noun
  • The joining of two coats of arms on one shield. 

  • (obsolete) In the sense of an enclosure, the calyx of a flower. In still older works, also spelt empalement (q.v.) 

  • A space fenced in, such as by palings, possibly in the form of an enclosure or cup. 

  • The act of torturing or executing someone by impaling them on a sharp stake. 

piercing

noun
  • An item of jewellery designed to be fitted through a piercing (sense 2). 

  • A hole made in the body so that jewellery can be worn through it. 

adj
  • Appearing to look deeply into; penetrating. 

  • Of sound, loud and sharp; shrill. 

  • Of temperature, extremely cold so that it penetrates through clothing and shelter. 

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