: having the form of or being gas
also : of or relating to gases
: lacking substance or solidity
: gassy sense 3
trick phrases and gaseous circumlocutionsEdwin Newman
gaseousness noun

Example Sentences

a substance changing from a liquid to a gaseous state a pompous professor known for his gaseous lectures that often put students to sleep
Recent Examples on the Web Nothing is more personally gaseous than to be heard calling for negotiations when the moment is unripe. WSJ, 4 Nov. 2022 In the Star Wars universe, Lando Calrissian runs Cloud City, a mining colony hovering at just the right height in the clouds of a gaseous planet so that its inhabitants can walk outside without a spacesuit. Eric Betz, Discover Magazine, 24 Apr. 2020 This is because gaseous methane, part of the planet’s chemical makeup, doesn’t appear blue to Webb’s Near-Infrared Camera (NIRCam). Katie Hunt, CNN, 21 Sep. 2022 In the absence of oxygen inside a digester, bacteria break down the compounds in sewage to create gaseous methane, which can be used to power gas stoves or converted to electricity. Discover Magazine, 29 Feb. 2012 There were reports of a gaseous odor, which was tracked to a leak in a PG&E natural gas line near the broken water main under the street, said Jon Baxter, spokesperson for the San Francisco Fire Department. Sam Whiting, San Francisco Chronicle, 7 Nov. 2022 The third-largest planet in our Solar System, Neptune often appears bright blue in images due to the presence of gaseous methane. Eric Berger, Ars Technica, 21 Sep. 2022 The gaseous planet will rise around sunset and look pearly white to the naked eye, said Patrick Hartigan, professor of physics and astronomy at Rice University in Houston. Megan Marples, CNN, 26 Sep. 2022 Rules about gaseous liquids in space requires, among other things, all pressure to remain contained in the bottle. Tim Newcomb, Popular Mechanics, 28 Sep. 2022 See More

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

Word History

First Known Use

1799, in the meaning defined at sense 1

Time Traveler
The first known use of gaseous was in 1799

Dictionary Entries Near gaseous

Cite this Entry

“Gaseous.” Dictionary, Merriam-Webster, Accessed 5 Feb. 2023.

Kids Definition


gas·​eous ˈgas-ē-əs How to pronounce gaseous (audio)
: having the form of or being gas
: of or relating to gas
: lacking solidity

Medical Definition


: having the form of or being gas
also : of or relating to gases

More from Merriam-Webster on gaseous

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