water vapor


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

Example Sentences

Recent Examples on the Web The satellite’s third instrument studied the makeup of the stratosphere, including levels of water vapor, nitrogen dioxide, aerosols and ozone, a gas that protects life on Earth by absorbing ultraviolet radiation from the sun. Will Sullivan, Smithsonian Magazine, 11 Jan. 2023 For its first 21 years in orbit, the spacecraft used three instruments to measure stratospheric concentrations of ozone, water vapor, nitrogen dioxide, and aerosols. Ariana Garcia, Chron, 11 Jan. 2023 The jet stream helps with development and transport of storm systems and water vapor across the globe. Max Golembo, ABC News, 11 Jan. 2023 Forloh’s proprietary welding process creates micro-perforations in the weld, each small enough to block liquid water, but large enough to allow water vapor—and body heat—to escape. Outside Online, 2 Dec. 2022 The pollution mostly consists of water vapor, carbon dioxide and sulfur dioxide. Zoe Sottile, CNN, 29 Nov. 2022 Other instruments, such as the infrared sounder on Aqua, capture temperature, water vapor, and dozens more variables globally each day. Bypaul Voosen, science.org, 21 Nov. 2022 This can lead to higher concentrations of methane, ozone, and water vapor in the atmosphere as hydrogen acts as a more potent greenhouse gas than carbon dioxide. Margo Oge, Forbes, 11 Aug. 2022 More rainfall is expected as the state’s atmospheric river forecast — rivers of water vapor in the sky pushed along by strong, hurricane-quick winds — persists. Evan Nicole Brown, The Hollywood Reporter, 10 Jan. 2023 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'water vapor.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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

Dictionary Entries Near water vapor

Cite this Entry

“Water vapor.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/water%20vapor. Accessed 27 Jan. 2023.

Kids Definition

water vapor

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

Medical Definition

water vapor

: water in a vaporous form especially when below boiling temperature and diffused (as in the atmosphere)
Last Updated: - Updated example sentences
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