water vapor


Definition of water vapor

: 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 The balls of water will evaporate into water vapor as the day warms. Ned Rozell, Anchorage Daily News, "The scents, sights and sounds of fall equinox in Alaska," 3 Oct. 2020 The process combines the gases with steam or air and then burns the mixture to produce water vapor and carbon dioxide. From Usa Today Network And Wire Reports, USA TODAY, "Playgrounds, airport testing, mask outreach: News from around our 50 states," 1 Oct. 2020 The technology relies on hydrogen, instead of gasoline, and produces electric current to run a vehicle’s motors, with water vapor the only exhaust gas. Paul A. Eisenstein, NBC News, "Fraud claims, DOJ probe and sexual abuse allegations cloud $2B deal between GM and Nikola truck startup," 30 Sep. 2020 Evaporation of water vapor from lungs also removes heat. Jim Williams, Star Tribune, "As the planet warms, the future of some birds is uncertain," 22 Sep. 2020 The water vapor would have traveled in the atmosphere and fallen on Mars’ poles and created tall, expansive ice caps. Theresa Machemer, Smithsonian Magazine, "Briny Underground Lakes May Be All That Remain of Martian Ocean," 30 Sep. 2020 With less water vapor to heat up, the sun's energy heats up the air instead. Chloe Jones, The Arizona Republic, "With 130 days at or over 100 degrees, Phoenix is having 2nd hottest year on record," 28 Sep. 2020 The process involves using a laser that melts a tiny bit from the ice surface and analyzing the chemicals released from each layer of water vapor. Lauren Kent, CNN, "How climate change affects pandemics," 28 Sep. 2020 Instead, today’s models have high-tech membranes with pores or gaps that are too small for liquid to penetrate but large enough for water vapor to pass through. Adrienne Donica And James Lynch, Popular Mechanics, "The Best Waterproof Hiking Boots, Tested," 21 Sep. 2020

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.

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First Known Use of water vapor

15th century, in the meaning defined above

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Time Traveler for water vapor

Time Traveler

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

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Statistics for water vapor

Last Updated

15 Oct 2020

Cite this Entry

“Water vapor.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/water%20vapor. Accessed 26 Oct. 2020.

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More Definitions for water vapor

water vapor


Medical Definition of water vapor

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

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