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Plural cirrocumuli (sîr'ō-kym'yə-lī')
A high-altitude cloud composed of a series of small, regularly arranged cloudlets in the form of ripples or grains. Cirrocumulus clouds generally form between 6,100 and 12,200 m (20,000 and 40,000 ft) and are composed exclusively of ice crystals. See illustration at cloud.