What does "buoy" mean?

Buoy: To keep from sinking in a fluid, as in water or air; to keep afloat; -- with up.

Additional senses

  1. 2.To support or sustain; to preserve from sinking into ruin or despondency. Those old prejudices, which buoy up the ponderous mass of his nobility, wealth, and title. Burke.
  2. 3.To fix buoys to; to mark by a buoy or by buoys; as, to buoy an anchor; to buoy or buoy off a channel. Not one rock near the surface was discovered which was not buoyed by this floating weed. Darwin.
  3. 4.To float; to rise like a buoy. "Rising merit will buoy up at last." Pope.

Sources