protection money vs sop

protection money

noun
  • Money paid, especially at regular intervals, to criminals or to corrupt officials who threaten to cause harm to the payer or to his or her business if the money is not paid. 

sop

noun
  • Something given or done to pacify or bribe. 

  • Something entirely soaked. 

  • A piece of turf placed in the road as a target for a throw in road bowling. 

  • A piece of solid food to be soaked in liquid food. 

  • Gravy. 

  • A weak, easily frightened or ineffectual person; a milksop 

verb
  • To soak in, or be soaked; to percolate. 

  • To steep or dip in any liquid. 

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