cirrostratus: Meaning and Definition of

cir•ro•stra•tus

1. a cloud of a class characterized by a composition of ice crystals and often by the production of halo phenomena and appearing as a whitish and usually somewhat fibrous veil, often covering the whole sky and sometimes so thin as to be hardly discernible: of high altitude, ab. 20,000–40,000 ft. (6000–12,000 m).