cumulus

American  

[kyoo-myuh-luhs] / ˈkyu myə ləs /

noun

plural

cumulus

1. a heap; pile.

2. a cloud of a class characterized by dense individual elements in the form of puffs, mounds, or towers, with flat bases and tops that often resemble cauliflower: as such clouds develop vertically, they form cumulonimbus.

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cumulus British  

/ ˈkjuːmjʊləs /

noun

1. a bulbous or billowing white or dark grey cloud associated with rising air currents Compare cirrus stratus

2. histology the mass of cells surrounding a recently ovulated egg cell in a Graafian follicle

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cumulus Scientific  

/ kyo̅o̅m′yə-ləs /

plural

cumuli

1. A dense, white, fluffy cloud with a flat base, a multiple rounded top, and a well-defined outline. The bases of cumulus clouds form primarily in altitudes below 2,000 m (6,560 ft), but their tops can reach much higher. Cumulus clouds are generally associated with fair weather but can also bring rain when they expand to higher levels. The clouds' edges are well-defined when they are composed of water droplets and fuzzy when made up of ice crystals.

2. See illustration at cloud

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Etymology

Origin of cumulus

1650–60; < New Latin ( Latin: mass, pile)