A dense, white, fluffy, flat-based cloud with a multiple rounded top and a well-defined outline, usually formed by the ascent of thermally unstable air masses.(noun)
A pile, mound, or heap.(noun)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "cumulus" in a sentence
"The word cumulus has a root similar to accumulate and means “piled up.”"
"The first stage of air mass thunderstorm development is called the cumulus stage (Figure 3)."
"This works to loosen a gel-like coating and sticky layer of cells known as the cumulus corona."