vapor pressure

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.

vapor pressure

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.

vapor pressure

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.

Word History and Origins

Origin of vapor pressure¹

Probably earlier than 1895–1900

Example Sentences

One way to measure this effect is through vapor pressure deficit, or VPD, which is the difference between how much water vapor the air could hold and how much is actually there.

From MIT Technology Review

Last year, the entire Southwest had a high vapor pressure deficit, and then a fortuitous ignition.

From Nautilus

The relative humidity is simply the ratio of the vapor pressure at the dew point to the pressure of saturated vapor (see Fig. 30).

From Project Gutenberg

Another factor contributing to the ease of handling of 1,2-butylene oxide is its vapor pressure.

From Project Gutenberg

Nearness to a coast does not mean uniform vapor pressure, for with wind alternating from sea to land, it means just the opposite.

From Project Gutenberg

Let me first repeat that evaporation increases with increased air currents and with decreased vapor pressure.

From Project Gutenberg

Now, the vapor pressure undergoes all manner of changes with the passing of storm centers and the changes of prevailing winds.

From Project Gutenberg