sudden death

Short definition from Wiktionary

Noun

1. 1
   Instantaneous, unexpected death not caused by violence or trauma.
2. 2
   A period or mode of play in which the next player or team to score wins instantly; often in an extra period of time following a tie at the end of the regular period of play.
3. 3
   A meal of a chicken freshly slaughtered and spatchcocked.
4. 4
   Used other than figuratively or idiomatically: see sudden, death.