Pronunciation: (boi'un-sē, bOO'yun-sē), [key]
1. the power to float or rise in a fluid; relative lightness.
2. the power of supporting a body so that it floats; upward pressure exerted by the fluid in which a body is immersed.
3. lightness or resilience of spirit; cheerfulness. Also,buoy'ance.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.