altostratus

[al-toh-strey-tuh s, -strat-uh s]
noun, plural al·to·stra·tus. Meteorology.
  1. a cloud of a class characterized by a generally uniform gray sheet or layer, lighter in color than nimbostratus and darker than cirrostratus: of medium altitude, about 8000–20,000 feet (2450–6100 meters).

Origin of altostratus

First recorded in 1890–95; alto- + stratus
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

British Dictionary definitions for altostratus

altostratus

noun plural -ti (-taɪ)
  1. a layer cloud at an intermediate height of about 2400 to 6000 metres (8000 to 20 000 feet)
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

altostratus in Science

altostratus

[ăl′tō-strătəs]
Plural altostrati (ăl′tō-strătī′)
  1. A mid-altitude cloud that extends in flat, smooth sheets or layers of varying thickness. Altostratus clouds generally form between 2,000 and 6,100 m (6,560 and 20,000 ft) and often produce long, steady rain showers. See illustration at cloud.
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