flash flood vs overkill

flash flood

noun
  • A sudden, rapid flood, usually of short duration and local impact. 

overkill

verb
  • To do something excessive to achieve a goal. 

  • To destroy something with more (nuclear) force than is required. 

  • To dispose of too many items because of too-high criteria of inspection. 

noun
  • An unnecessary excess of disposal because of too high criteria of inspection. 

  • Destruction beyond what is necessary to kill, especially in murder. 

  • A destructive capacity that exceeds that needed to destroy an enemy; especially with nuclear weapons. 

  • An unnecessary excess of whatever is needed to achieve a goal. 

How often have the words flash flood and overkill occurred in a corpus of books? (source: Google Ngram Viewer )