noun · 2 senses · updated from the 2026-07-25 local source snapshot
Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.
Sound
Pronunciation
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Received-Pronunciation:/ˌsɪɹə(ʊ)ˈkjuːmjʊləs/
General-American:/ˌsɪɹoʊˈkjumjələs/
General-American:Recorded audio is listed in the source snapshot.
rhymes with -uːmjʊləs
1
noun
Meaning 1
A principal high-level cloud type appearing as a thin, white patch of cloud without shadows, composed of very small droplets in the form of grains or ripples. The elements may be merged or separate, and more or less regularly arranged; they subtend an angle of less than 1° when observed at an angle of more than 30° above the horizon. Holes or rifts often occur in a sheet of cirrocumulus.
Definition source: English Wiktionary via Wiktextract