stratus

plural strati

1. uncountableusuallyclimatologyA principal, low-level cloud type in the form of a gray layer with a rather uniform base, usually not associated with precipitation, and capable of producing corona phenomena and a weak, uniform luminance.

   [page 99] Stratus. […] A widely extended, continuous, horizontal sheet, increasing from below. […] [page 357] When a stratus covers the ground at sun-rise, however, we often see it collect into cumuli upon the evaporation of that part of it which is immediately contiguous to the earth: […]

   1803 July, Luke Howard, “XVIII. On the Modifications of Clouds, and on the Principles of Their Production, Suspension, and Destruction; being the Substance of an Essay Read before the Askesian Society in the Session 1802–3.”, in Alexander Tilloch, editor, The Philosophical Magazine and Journal: Comprehending the Various Branches of Science, the Liberal and Fine Arts, Agriculture, Manufactures, and Commerce, volume XVI, number 62, London: […] [Richard Taylor] for Alexander Tilloch; and sold by Messrs. Richardson, […], →ISSN, →OCLC, pages 99 and 357

   Synonyms: St