noun
game point
Used in sports such as tennis, badminton, or volleyball to refer to the point that could win the game for a player or team.
このポイントを取ればゲームポイントだ。
If I win this point, it's game point.
マッチポイント is match point (the point that wins the match), while ゲームポイント is game point (the point that wins the game within a match).
Loanword from English 'game point'.