The Collaborative International Dictionary of English v.0.48:

Buoy \Buoy\, v. t. [imp. & p. p. Buoyed; p. pr. & vb. n.
   Buoying.]
   1. To keep from sinking in a fluid, as in water or air; to
      keep afloat; -- with up.
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   2. To support or sustain; to preserve from sinking into ruin
      or despondency.
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            Those old prejudices, which buoy up the ponderous
            mass of his nobility, wealth, and title. --Burke.
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   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.
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            Not one rock near the surface was discovered which
            was not buoyed by this floating weed. --Darwin.
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