cumul-

1 of 2

combining form

variants or cumuli- or cumulo-

: cumulus and

cumulonimbus

cumulus

2 of 2

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 of cumul-

Noun

• accumulation
• collection
• mixture
• assemblage
• jumble

Examples of cumul- in a Sentence

Noun

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

Recent Examples on the Web

Noun

Throughout the morning, Lisius — and chasers who had fanned out across North Texas — waited for the drifting cumulus clouds to rise far enough to become a tornado-producing supercell thunderstorm. —Emily Holshouser may 19, Fort Worth Star-Telegram, 19 May 2026

Contain cumulus clouds within 10 nautical miles of the flight path that meet certain distance and height criteria. —Brandi D. Addison, USA Today, 31 Mar. 2026

There is currently a 20% chance of a weather violation on Wednesday due to potential cumulus clouds in the lower troposphere. —Josh Dinner, Space.com, 29 Mar. 2026

Low-level clouds, like cumulus and stratocumulus, could block out large portions of the sky. —Newsroom Meteorologist, Austin American Statesman, 2 Mar. 2026

Word History

Etymology

Combining form

New Latin, from Latin cumulus

Noun

Latin

First Known Use

Noun

1659, in the meaning defined at sense 1