Buoy'ant, a.

a. [From buoy, v. i.]

1. Having the quality of rising or floating in a fluid; tending to rise or float; as, iron is buoyant in mercury. “Buoyant on the flood.” Pope.
2. Bearing up, as a fluid; sustaining another body by being specifically heavier.

I swam with the tide, and the water under me was buoyant. Dryden. 3. Vivacious; cheerful; as, a buoyant disposition; buoyant spirits.