cirrus

noun

cir·​rus ˈsir-əs How to pronounce cirrus (audio)
plural cirri ˈsir-ˌī How to pronounce cirrus (audio)
1
2
: a slender usually flexible animal appendage or projection: such as
a
: an arm of a barnacle
b
: a filament of a crinoid
c
: a fused group of cilia functioning like a limb on some protozoans
d
: the male copulatory organ of various invertebrate animals
3
: a high wispy white cloud usually of minute ice crystals formed at altitudes between about 20,000 and 40,000 feet (6,000 and 12,000 meters) see cloud illustration

Examples of cirrus in a Sentence

Recent Examples on the Web The water vapor and cirrus clouds that planes trail behind them look picturesque, but their warming impact is three times that of carbon. Liza Featherstone, The New Republic, 28 Dec. 2022 An orographic cirrus cloud formation on the eastern side of the Rocky Mountains, as seen at night by the Suomi NPP satellite on 12/18/13. Tom Yulsman, Discover Magazine, 20 Dec. 2013 Aside from those brief glimpses through the storm, the cirrus clouds resembled a flat blanket beneath the deep blue sky. Ian Jamesstaff Writer, Los Angeles Times, 1 Feb. 2023 Their beautiful colors form when the sun is at a higher elevation than 58 degrees, causing light to be refracted through the ice crystals in cirrus clouds. Allison Futterman, Discover Magazine, 22 Dec. 2021 The wind-shear phenomenon can occur in wispy cirrus clouds or even clear air near thunderstorms, as differences in temperature and pressure create powerful currents of fast-moving air. Audrey McAvoy, USA TODAY, 19 Dec. 2022

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

Word History

Etymology

New Latin, from Latin, curl

First Known Use

1708, in the meaning defined at sense 1

Time Traveler
The first known use of cirrus was in 1708

Dictionary Entries Near cirrus

Cite this Entry

“Cirrus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/cirrus. Accessed 28 Mar. 2024.

Kids Definition

cirrus

noun
cir·​rus ˈsir-əs How to pronounce cirrus (audio)
plural cirri ˈsi(ə)r-ˌī How to pronounce cirrus (audio)
: a thin white cloud usually of tiny ice crystals formed at altitudes about 20,000 to 40,000 feet (6,000 to 12,000 meters)

Medical Definition

cirrus

noun
cir·​rus ˈsir-əs How to pronounce cirrus (audio)
plural cirri ˈsi(ə)r-ˌī How to pronounce cirrus (audio)
: a slender usually flexible animal appendage: as
a
: a fused group of cilia functioning like a limb on some protozoans
b
: the male copulatory organ of some worms

More from Merriam-Webster on cirrus

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