decider
n. B2 Upper Intermediate US //ˌdɪˈsaɪdɝ// UK //dɪsˈaɪdɐ// de·cider
n. the final event or moment that decides the winner of a competition. It is the last thing that happens when a game or race is tied.
n. the final event or factor that determines the outcome of a competition or contest. Often used in sports to describe a sudden-death match or a final point.
The final set was the decider in the tennis match.
After the score was tied at the end of regulation time, the coach called for the decider to settle the championship.
In many high-stakes tournaments, the decider is not just a single point but a series of high-pressure plays that test the mental fortitude of the athletes.