Simple Definition of cumulus

from our Learner's Dictionary

cumulus

noun

ˈkjuːmjələs

plural cumuli ˈkjuːmjəˌlaɪ

technical : a type of thick cloud that is rounded on top and has a flat base

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“Cumulus.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/cumulus. Accessed 22 Jun. 2026.

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