- a dispersion, in air, of molecules of water, especially as produced by evaporation at ambient temperatures rather than by boiling.Compare steam(def 2).
Origin of water vapor
First recorded in 1875–80
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for water vapor
The resulting products of this combustion, if it is complete, are carbon dioxide and water-vapor.Artificial Light
The warmth and the habitability of the earth's surface is due to the presence of water-vapor and carbon-dioxide in the atmosphere.Astronomy for Young Folks
Isabel Martin Lewis
In fact, every minute thousands of barrels of water-vapor are rising into the atmosphere from the surface of the ocean.
The total volume of air (which may be designated as V) includes the volumes of carbon dioxide, water-vapor, oxygen, and nitrogen.
Any variations in the residual amount of carbon dioxide or water-vapor likewise affect the oxygen.
- Water in its gaseous state, especially in the atmosphere and at a temperature below the boiling point. Water vapor in the atmosphere serves as the raw material for cloud and rain formation. It also helps regulate the Earth's temperature by reflecting and scattering radiation from the Sun and by absorbing the Earth's infrared radiation. See also vapor.
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