buoyancy

noun

buoy·​an·​cy ˈbȯi-ən(t)-sē 

ˈbü-yən(t)-

1

a

: the tendency of a body to float or to rise when submerged in a fluid

testing an object's buoyancy

b

chemistry : the power of a fluid to exert an upward force on a body placed in it

the buoyancy of water

also : the upward force exerted

2

: the ability to recover quickly from depression or discouragement : resilience

his buoyancy of spirit

3

: the property of maintaining a satisfactorily high level (as of prices or economic activity)

betting that the economy will maintain its buoyancy

Examples of buoyancy in a Sentence

the natural buoyancy of cork

The swimmer is supported by the water's buoyancy.

We hope that the economy will maintain its buoyancy.

Recent Examples on the Web

Thus began a rite of spring for the Royals, who remain graced by Perez’s buoyancy and Terminator-like durability. —Kansas City Star, 25 Mar. 2026

This modularity, along with the energy-efficient buoyancy propulsion system, provides the Slocum with a most flexible system for integrating sensors for optimal ocean observation, according to Teledyne Webb Research. —Prabhat Ranjan Mishra, Interesting Engineering, 20 Mar. 2026

Proper buoyancy would have required roughly 22 pounds. —Madison Dapcevich, Outside, 19 Mar. 2026

This holds tanks largely filled with fresh water to maintain the platform’s buoyancy in the salty ocean. —IEEE Spectrum, 3 Mar. 2026

Word History

Etymology

see buoy entry 1

First Known Use

1713, in the meaning defined at sense 1a

Kids Definition

buoyancy

noun

buoy·​an·​cy ˈbȯi-ən-sē 

ˈbü-yən-

1

: the tendency of a body to float or to rise when in a fluid

the buoyancy of a cork in water

2

: the power of a fluid to put an upward force on a body placed in it

the buoyancy of seawater