knock back vs swig

knock back

verb
  • To drink an alcoholic beverage swiftly or often. 

  • To stun; to surprise. 

  • To press or knead (dough) so as to remove air bubbles. 

  • To reject; to refuse. 

swig

verb
  • To drink (usually by gulping or in a greedy or unrefined manner); to quaff. 

  • To take up the last bit of slack in rigging by taking a single turn around a cleat, then hauling on the line above and below the cleat while keeping tension on the line. 

noun
  • A long draught from a drink. 

  • Warm beer flavoured with spices, lemon, etc. 

  • A tackle with ropes which are not parallel. 

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