- a heap; mass; pile
- the type of bright, billowy cloud with a dark, flat base, that develops vertically through all cloud levels and consists mostly of water droplets
Origin of cumulusL, a heap ; from Indo-European an unverified form ?u-melos, a swelling, increase ; from base an unverified form ?eu-, a swelling from source cave
- A dense, white, fluffy, flat-based cloud with a multiple rounded top and a well-defined outline, usually formed by the ascent of thermally unstable air masses.
- A pile, mound, or heap.
Origin of cumulusLatin, heap; see keu&schwa;- in Indo-European roots.
From Latin cumulus.