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cirrus

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noun, cir·rus \ˈsir-əs\

Simple Definition of cirrus

  • : a thin type of cloud that forms high in the sky

Source: Merriam-Webster's Learner's Dictionary

Full Definition of cirrus

plural cirri play \ˈsir-ˌī\

  1. 1 :  tendril

  2. 2 :  a slender usually flexible animal appendage or projection: 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. 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

Origin of cirrus

New Latin, from Latin, curl


First Known Use: 1708

Rhymes with cirrus


CIRRUS Defined for Kids

cirrus

play
noun cir·rus \ˈsir-əs\

Definition of cirrus for Students

plural cirri \ˈsir-ī\

  1. :  a thin white cloud of tiny ice crystals that forms at a very high altitude




Medical Dictionary

cirrus

play
noun cir·rus \ˈsir-əs\

Medical Definition of cirrus

plural cirri \ˈsi(ə)r-ˌī\play

  1. :  a slender usually flexible animal appendage: asa:  a fused group of cilia functioning like a limb on some protozoansb:  the male copulatory organ of some worms



Illustration of cirrus


Learn More about cirrus


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