water vapor

American  

noun

1. a dispersion, in air, of molecules of water, especially as produced by evaporation at ambient temperatures rather than by boiling.

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water vapor Scientific  

1. 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.

2. See also vapor

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Etymology

Origin of water vapor

First recorded in 1875–80

Example Sentences

A familiar physical example appears at the critical point of water, defined by a precise temperature and pressure at which liquid water and water vapor become indistinguishable.

From Science Daily

The tower is bristling with high-tech instruments - sensors that track almost everything happening between the forest and the atmosphere: water vapor, carbon dioxide, sunlight, and essential nutrients like nitrogen and phosphorus.

From BBC

What Enceladus does is akin to a volcano hurling lava into space -- except the ejecta are plumes of water vapor and ice.

From Science Daily

Until now, scientists believed that heat loss was limited to the south pole, where geysers shoot water vapor and ice particles into space.

From Science Daily

Unlike fossil fuels, which emit planet-warming carbon, hydrogen simply produces water vapor when burned.

From Barron's