What does "buoyancy" mean?

Buoyancy: (Physics) The upward pressure exerted upon a floating body by a fluid, which is equal to the weight of the body; hence, also, the weight of a floating body, as measured by the volume of fluid displaced. Such are buoyancies or displacements of the different classes of her majesty's ships. Eng. Cyc.

Additional senses

  1. 2.Cheerfulness; vivacity; liveliness; sprightliness; -- the opposite of Ant: heaviness; as, buoyancy of spirits.

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