cumulus

noun cu·mu·lus \ ˈkyü-myə-ləs \

Definition of cumulus

plural cumuli play \ˈkyü-myə-ˌlī, -ˌlē\

1 :heap, accumulation

[New Latin, from Latin]

:a dense puffy cloud form having a flat base and rounded outlines often piled up like a mountain — see cloud illustration

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Examples of cumulus in a Sentence

the cumulus of sundry things that fill up one's attic and somehow sum up a lifetime of experiences

Recent Examples of cumulus from the Web

The day will start off sunny with afternoon cumulus clouds developing.

— thomas novelly, The Courier-Journal, "Could clouds block the once-in-a-lifetime eclipse in Kentucky?," 15 Aug. 2017
In Southern California, the wet weather is mostly confined to the deserts and mountains, and buildups of cumulus clouds over the mountains can often be seen from the coast.

— paul duginski, latimes.com, "What's behind Southern California's summer rain and thunderstorms?," 3 Aug. 2017
Skies remain mostly sunny aside from the normal fair-weather cumulus, as highs head into the upper 80s to near 90.

— brian jackson, Washington Post, "D.C.-area forecast: Relatively nice today; heat and humidity build again this week," 16 July 2017
An orbit of brushed up brunette framed Solange Knowles’s summer selfie, her curly cumulus surrounding a nearly-naked face that demonstrated the importance of power brows.

— calin van paris, Vogue, "The 10 Best Beauty Instagrams of the Week: Sean Combs, Solange Knowles, and More," 2 July 2017
Fair weather waterspouts usually form along a dark, flat base of a line of developing cumulus clouds.

— lisa dejong, cleveland.com, "Lake Erie waterspouts seen near Cleveland on Monday (photo)," 26 June 2017
This will cause relatively warm, 70-degree air at ground level to ascend into towering cumulus clouds.

— tom skilling, chicagotribune.com, "Springlike weather to persist through Monday," 24 June 2017
Through tonight: Some puffy cumulus clouds are popping up this afternoon ahead of a weak cold front to our north.

— greg porter, Washington Post, "PM Update: Clear and comfortable tonight. And Saturday’s a gem, too.," 2 June 2017
By Sunday, a nasty little lightning bolt has appeared under the cartoon cumulus.

— doug maccash, NOLA.com, "The 5 finest features of Bayou Country Superfest in New Orleans," 24 May 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'cumulus.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of cumulus

Latin

NEW! Time Traveler

First Known Use: 1659

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cumulus Synonyms

Synonyms

accretion, assemblage, collection, cumulation, accumulation, gathering, lodgment (or lodgement), pileup

CUMULUS Defined for English Language Learners

cumulus

noun

Definition of cumulus for English Language Learners

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

CUMULUS Defined for Kids

cumulus

noun cu·mu·lus \ ˈkyü-myə-ləs \

Definition of cumulus for Students

plural cumuli \-ˌlī, -ˌlē\

:a massive cloud form having a flat base and rounded outlines often piled up like a mountain

Medical Dictionary

cumulus

noun cu·mu·lus \ ˈkyü-myə-ləs \

medical Definition of cumulus

plural cumuli play \-ˌlī, -ˌlē\

:the projecting mass of granulosa cells that bears the developing ovum in a graafian follicle — called also discus proligerus

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See words that rhyme with cumulus Thesaurus: All synonyms and antonyms for cumulus Spanish Central: Translation of cumulus Nglish: Translation of cumulus for Spanish speakers Britannica.com: Encyclopedia article about cumulus

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CUMULUS Defined for English Language Learners

cumulus

Definition of cumulus for English Language Learners

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cumulus

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cumulus

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