cu·​mu·​lo·​nim·​bus ˈkyü-myə-(ˌ)lō-ˈnim-bəs How to pronounce cumulonimbus (audio)
: cumulus cloud having a low base and often spread out in the shape of an anvil extending to great heights see cloud illustration

Examples of cumulonimbus in a Sentence

Recent Examples on the Web In an average year, about 800 tornadoes are reported nationwide, and the violent rotating columns of air that come in contact with land and a cumulonimbus cloud or, in rare cases, a cumulus cloud, result in about 80 deaths and 1500 injuries, according to the National Weather Service. Frank Witsil, Detroit Free Press, 26 July 2023 How hail forms Hail forms inside cumulonimbus clouds, which produce thunder, lightning and hail. USA TODAY, 17 July 2023 The weather setup for Wednesday will be chock full of cirrus, cumulus and cumulonimbus clouds bubbling up across Northern California. Gerry Díaz, San Francisco Chronicle, 3 May 2023 William Rankin was flying his F-8 fighter jet over a cumulonimbus when the engine failed. Rebecca Coffey, Discover Magazine, 29 Jan. 2012 The clouds typically form as a result of air turbulence within large cumulonimbus structures. Travis Fedschun, Fox News, 30 Apr. 2020 Cloud nine is a cumulonimbus cloud that can rise to the lofty height of 6.2 miles, as high as a cloud can be. Richard Lederer, San Diego Union-Tribune, 19 Oct. 2019 The eyewall is the band or ring of cumulonimbus clouds that surround the eye of the storm. Molly Rubin, Quartz, 12 July 2019 The dense cumulonimbus clouds threatened thunder and lightning. Denise Coffey,, 28 June 2019 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'cumulonimbus.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


New Latin

First Known Use

1887, in the meaning defined above

Time Traveler
The first known use of cumulonimbus was in 1887

Dictionary Entries Near cumulonimbus

Cite this Entry

“Cumulonimbus.” Dictionary, Merriam-Webster, Accessed 7 Dec. 2023.

Kids Definition


cu·​mu·​lo·​nim·​bus ˌkyü-myə-lō-ˈnim-bəs How to pronounce cumulonimbus (audio)
: a cumulus cloud that has a low base and that is often spread out in the shape of an anvil extending to great heights

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