break-off vs parting

break-off

noun
  • A break, discontinuance, or interruption 

  • That which breaks off, or is broken off 

  • The first shot in a game of snooker or other cue-game 

verb
  • To play the first shot in a game of snooker 

parting

noun
  • The act of parting or dividing; the state of being parted; division; separation. 

  • The surface of the sand of one section of a mould where it meets that of another section. 

  • A joint or fissure, as in a coal seam. 

  • The dividing line formed by combing the hair in different directions; part (US) 

  • The separation and determination of alloys; especially, the separation, as by acids, of gold from silver in the assay button. 

  • A farewell, the act of departing politely. 

  • The breaking, as of a cable, by violence. 

  • Lamellar separation in a crystallized mineral, due to some other cause than cleavage, as to the presence of twinning lamellae. 

How often have the words break-off and parting occurred in a corpus of books? (source: Google Ngram Viewer )