v.1. To keep something or someone aloft or afloat: Air currents helped buoy up the glider. The life jacket buoyed me up until I was rescued.
2. To keep something at a high level; support something: The advertising campaign buoyed up their sales through the summer. The athlete's endorsement buoyed the politician up.
3. To hearten or inspire someone or something: The cheering fans buoyed up the team's spirit. Your kind words have buoyed me up.