Definition of cirrostratus in English:

cirrostratus

Pronunciation /ˌsirōˈstradəs/ /ˌsɪroʊˈstrædəs/ /ˌsirōˈstrādəs/ /ˌsɪroʊˈstreɪdəs/

noun

  • Cloud forming a thin, more or less uniform, semitranslucent layer at high altitude, usually 16,500–45,000 feet (5–13 km).

    ‘The cloud most suited to halo formation is cirrostratus, which is most commonly observed well ahead of a developing frontal system.’
    • ‘Halos form when light from the sun or moon is refracted by ice crystals associated with thin, high-level clouds (like cirrostratus clouds).’
    • ‘Stratosphere air contains little water vapor or dust; only wispy cirrostratus clouds streak the distant sky.’