a death blow

death blow

1. A hit or impact that causes immediate death. The warrior swiftly dealt a death blow to his adversary on the battlefield.
2. An event that causes the abrupt end of something. His arrest and subsequent conviction was a death blow to his successful career as an attorney. Despite the company's recent success, the massive recall proved to be its death blow.
See also: blow, death
Farlex Dictionary of Idioms.

a death blow

If something is a death blow to a process, situation, or organization, it causes it to end or fail. This could deal a death blow to the collapsing national economy. They warned that the deportations would be a death blow to the peace process.
See also: blow, death
Collins COBUILD Idioms Dictionary, 3rd ed.
See also:
  • death blow
  • be a square peg
  • be a square peg (in a round hole)
  • a political football
  • domino
  • domino effect
  • a domino effect
  • (something) is no object
  • be in good with (someone)
  • by the same token