cumulus

noun

cu·​mu·​lus ˈkyü-myə-ləs 

plural cumuli ˈkyü-myə-ˌlī 

-ˌlē

1

: heap, accumulation

2

[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

Synonyms

• accretion
• accumulation
• assemblage
• collection
• cumulation
• gathering
• lodgment
• lodgement
• pileup

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 on the Web

The forecast calls for a 75% chance of acceptable weather conditions, with cumulus cloud cover being the primary concern (as of the time this article was published). —Robert Z. Pearlman, Space.com, 16 June 2025

The Puzzle 10 collection includes re-editions like the Cloud bag of spring 2017, printed with dreamy cumulus across each angled panel, and the Polka edition, whose bold intarsia dots nodded to mid-century couture and 19th-century novels alike. —Lilah Ramzi, Vogue, 29 May 2025

The cumulus congestus cloud rises dramatically in the image, casting a dark shadow over the landscape below. —Josh Hammer, Newsweek, 23 Dec. 2024

Cotton ball cumulus clouds Clouds that look like cartoon cotton balls or cauliflower are made up of tiny liquid water droplets and are called cumulus clouds. —Ross Lazear, The Conversation, 3 Mar. 2025

Word History

Etymology

Latin

First Known Use

1659, in the meaning defined at sense 1

Rhymes for cumulus

• tumulus

Kids Definition

cumulus

noun

cu·​mu·​lus ˈkyü-myə-ləs 

plural cumuli -ˌlī 

-ˌlē

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

Medical Definition

cumulus

noun

cu·​mu·​lus ˈkyü-myə-ləs 

plural cumuli -ˌlī, -ˌlē 

: the projecting mass of granulosa cells that bears the developing ovum in a graafian follicle

called also discus proligerus