Businessman: “I can’t believe Shirley got us such a good price! She’s really on her game!”

When you are on your game, you are doing something to the best of your ability. “Game” refers to sports, but you can say this about any skill. If you are off your game, you are not doing the best job you can. It’s not that you are not trying, but you are not living up to your full potential.


「On your game」は、自分の才能を最大限に出せている状態です。「ゲーム」はスポーツに引用されますが、どんなスキルについても言えます。「Off your game」は、実力を出せていないという意味です。頑張っていないわけではないですが、才能を十分発揮できていない状態です。