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.
The simulated collision matched a roughly 17-kilometer-wide impactor slamming into Mercury at speeds of up to 30 kilometers per second, generating a dense, temporary atmosphere rich in water vapor around the planet, the team reports in the new study. Sharmila Kuthunur, Space.com, 28 May 2026 The new findings, published in the journal Astronomy and Astrophysics, suggest that earlier observations may have been influenced by statistical uncertainty rather than definitive signs of erupting water vapor. Jamie Carter, Forbes.com, 26 May 2026 Landings can also release water vapor, carbon dioxide and other gases into the lunar exosphere – an extremely thin layer of atoms hovering above the surface – and create a temporary atmosphere. Parvathy Prem, The Conversation, 14 May 2026 Water also exists in the air as water vapor, in rivers and lakes, in icecaps and glaciers, in the ground as soil moisture and in aquifers, and even in you and your dog. Kurt Snibbe, Oc Register, 8 May 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 4 Jun. 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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