water vapor

noun

: water in a vaporous form especially when below boiling temperature and diffused (as in the atmosphere)

Examples of water vapor in a Sentence

Recent Examples on the Web
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Thanks to the return of southeasterly winds carrying more atmospheric moisture from the Gulf Coast into Central Texas, surface dew point temperatures (an indicator of water vapor saturation in the air) will steadily increase ahead of a potentially rainy weekend, forecasters said. Roberto Villalpando, Austin American Statesman, 8 Apr. 2026 Near sea level, where atmospheric pressure can be higher than on the side of a mountain, the weight of the atmosphere forces water vapor molecules into a smaller space, which has the effect of increasing relative humidity by building up the density of overall moisture. John P. Rafferty, Encyclopedia Britannica, 7 Apr. 2026 The presence of gases such as methane, ammonia, and water vapor may further stabilize these environments, significantly extending the potential window for habitability. Jijo Malayil, Interesting Engineering, 22 Mar. 2026 At the same time, a warmer atmosphere holds more water vapor, which is then released in fewer, more extreme rainstorms. Clara Harter, Los Angeles Times, 20 Mar. 2026 See All Example Sentences for water vapor

Word History

First Known Use

15th century, in the meaning defined above

Time Traveler
The first known use of water vapor was in the 15th century

Browse Nearby Words

Cite this Entry

“Water vapor.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/water%20vapor. Accessed 11 Apr. 2026.

Kids Definition

water vapor

noun
: water in a gaseous form especially when below boiling temperature and spread through the atmosphere

Medical Definition

water vapor

noun
: water in a vaporous form especially when below boiling temperature and diffused (as in the atmosphere)
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