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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Acid rain is formed when sulfur dioxide and nitrogen oxides released into the atmosphere react with oxygen, water and other chemicals to form sulfuric and nitric acids, which can dissolve in water vapor. Andrea Thompson, Scientific American, 22 Apr. 2026 For every one degree increase in air temperature, the atmosphere can hold about 4% more water vapor. Jacob Wycoff, CBS News, 17 Apr. 2026 Moist air contains a higher proportion of water vapor, which is lighter than the nitrogen and oxygen that make up most of the atmosphere. Brandi D. Addison, USA Today, 16 Apr. 2026 During its observations, MAJIS identified infrared emissions from water vapor and carbon dioxide molecules. Robert Lea, Space.com, 15 Apr. 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 29 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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