tiebreaker

[ tahy-brey-ker ]
/ ˈtaɪˌbreɪ kər /

noun

a system for breaking a tie score at the end of regulation play by establishing a winner through special additional play, usually of a fairly short duration, as in tennis and soccer.
Often tie·break.

Origin of tiebreaker

First recorded in 1960–65; tie + breaker1

British Dictionary definitions for tie-break

tie-break

tie-breaker

/ (ˈtaɪˌbreɪkə) /

noun

tennis a method of deciding quickly the result of a set drawn at six-all, usually involving the playing of one deciding game for the best of twelve points in which the service changes after odd-numbered points
any contest or game played to decide a winner when contestants have tied scores