hebetate vs pipe down

hebetate

verb
  • To render obtuse; to dull; to blunt. 

adj
  • obtuse; dull 

  • Having a dull or blunt and soft point 

pipe down

verb
  • To be quiet; to refrain from being noisy. 

  • To dismiss from muster, as a ship's company. 

  • Of a man, to have penetrative sex with a woman. 

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