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Descriptive of clouds composed of small particles, mostly ice crystals, which are fairly widely dispersed, usually resulting in relative transparency and whiteness and often producing halo phenomena not observed with other cloud forms.
Having the form of a cirrus; generally applied to a prolonged, slender process.
All species and varieties of cirrus, cirrocumulus, and cirrostratus clouds. These are high clouds composed mostly (or entirely) of small ice crystals, which are normally transparent and white in color. These clouds often produce halo phenomena not observed with other cloud forms.