vapor pressure

American  

noun

1. the pressure exerted by the molecules of a vapor, especially that part of the total pressure exerted by vapor in a mixture of gases, as by water vapor in air.

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vapor pressure Scientific  

1. The pressure exerted by a vapor on the solid or liquid phase with which it is in equilibrium. At pressures lower than the vapor pressure, more atoms or molecules of the liquid or solid vaporize and escape from the surface of the liquid or solid than are absorbed from the vapor, resulting in evaporation. At the vapor pressure the exchange is equal and there is no net evaporation.

2. Also called evaporation pressure

3. The pressure exerted by water vapor in the atmosphere.

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vapor pressure Cultural  

1. In physics and chemistry, the atmospheric pressure that would be exerted by any single component of a gas if that component were the only one present. For example, the vapor pressure of oxygen in the atmosphere of the Earth is the pressure that would exist if everything but oxygen were removed. The total atmospheric pressure is the sum of the vapor pressures of all the materials in the atmosphere.

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Etymology

Origin of vapor pressure

Probably earlier than 1895–1900

Compare meaning

How does vapor-pressure compare to similar and commonly confused words? Explore the most common comparisons:

• vapor pressure vs. boiling point

Example Sentences

Well, what I would say is the year 2000 in my mind represents a clear transition in things like vapor pressure deficit, that feeds into vegetation being a lot drier in California.

From Los Angeles Times • Jan. 30, 2025

The water working up through the soil under the concrete created a vapor pressure that caused the paint to fail.

From Seattle Times • Mar. 25, 2024

In general the differences in those averages were strongly associated with vapor pressure deficit or VPD, basically the drying power of the atmosphere.

From Science Daily • Dec. 28, 2023

Scientists call this phenomenon the vapor pressure deficit.

From Scientific American • Aug. 23, 2023

The vapor pressure of 1,2-butylene oxide is only 207.0 mm Hg at 25� C. as opposed to 1,292.0 for ethylene oxide and 569.0 for propylene oxide.

From U.S. Patent 4,293,314: Gelled Fuel-Air Explosive October 6, 1981. by Stull, Bertram O.