knock down vs rough-and-tumble

knock down

verb
  • To hit or knock (something or someone), intentionally or accidentally, so that it falls. 

  • To drink fast. 

  • To disassemble for shipment. 

  • To reduce the price of. 

  • To demolish. 

  • To approve a drinking toast by banging glasses on the table. 

  • At an auction, to declare (something) sold with a blow from the gavel. 

rough-and-tumble

verb
  • Engage in rough-and-tumble activity 

adj
  • active, vigorous and rough, with the possibility of harm 

  • highly competitive 

noun
  • An environment of rough activity 

  • Rough activity; fighting or brawling; a fight. 

  • A person who characteristically engages in such activity 

How often have the words knock down and rough-and-tumble occurred in a corpus of books? (source: Google Ngram Viewer )