buoyancy
BOY-un-see
/ˈbɔɪənsi/
The ability or tendency to float in water or air or some other fluid.
In sports, it refers to a swimmer's natural ability to stay high on the water's surface, which reduces drag.
The story behind the word. The word traces back to the Spanish 'boyar', meaning to float. It is related to the word 'buoy', those floating markers you see in harbors.
Word relationships
- floatability: A more literal but less formal term for the same concept.
- heaviness: The quality of being heavy, which leads to sinking.
Commonly confused with
- density: Density is a property of the object; buoyancy is the resulting force from the fluid.
Word family
- buoyant (adjective): Able to float.
Collocations
- neutral buoyancy
- positive buoyancy
- buoyancy aid
Example sentences
- "The buoyancy of an object depends on the density of the fluid it is in." Physics textbook
- "Wearing a wetsuit can significantly improve a swimmer's buoyancy in open water." Swimming coaching
Memory hook
A 'buoy' stays up because of 'buoyancy'. Buoy = Float.
When not to use
Avoid using it to mean 'happiness' in a formal sports context, though it can mean 'cheerfulness' in literature.
Fun facts
- Salt water provides more buoyancy than fresh water because it is denser.
Related words
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