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

When the sun hits the painted wood and warms it, it creates a difference in vapor pressure.

From Seattle Times • May 20, 2024

The researchers also compared fire occurrences to weather patterns and found clear associations between fires, high temperatures and vapor pressure deficit, which is an indicator of plant water stress.

From Science Daily • May 2, 2024

The study points to record-breaking temperatures that have decreased the relative humidity of the atmosphere, increasing the occurrence of "vapor pressure deficit."

From Scientific American • May 31, 2023

In such a cellar the vapor pressure of the air is not only greater but is less influenced by the shifting vapor pressure of the outside air.

From The Dollar Hen by Hastings, Milo M. (Milo Milton)