1. The final moment before one dies; the last period of one's life. Even though my grandfather's lungs were riddled with cancer and emphysema, he remained a smoker until his very last breath.

2. The last moment before a person or group ultimately fails or must give up. We might be down by 10 points, but we have to keep on fighting to the last breath! Even as their stocks plummeted, the company maintained a public image of success right to their last breath.